Post on 10-Jan-2019
Instituto Politécnico de Setúbal
Escola Superior de Tecnologia
de Setúbal
Controlo de um sistema articulado com dois graus de liberdade
Pedro Silva
Nº: 4064
Luís Rita
Nº: 3468
Projecto final para obtenção do grau de Bacharel em Engenharia de Electrónica
e Computadores
Outubro de 2003
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Projecto Final realizado sob a orientação do
Professor António Abreu
Departamento de Engenharia Electrotécnica
Escola Superior de Tecnologia de Setúbal
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RESUMO
Este trabalho tem como objectivo a construção e controlo de um sistema com 2
graus de liberdade: azimute e elevação.
O controlo incide sobre 2 motores passo-a-passo, e a informação na qual se
baseia o controlo é a luminosidade proveniente de quatro sensores.
Assim, o sistema procura e segue fontes de luminosidade.
PALAVRAS CHAVE
• Sensor
• Conversor
• Controlo
• Motor passo-a-passo
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ABSTRACT
The objective of this is the construction and control of a system with two
degrees of freedom: azimuth and elevation.
The control goes straight to two engines step by step, and is based on the
brightness of four sensors.
So, the system searches for and follows the source of the brightness.
KEYWORDS
• Sensor
• Converter
• Control
• Engine step by step
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AGRADECIMENTOS
Desejamos prestar os nossos agradecimentos ao nosso orientador Prof. António
Abreu, por se ter empenhado na orientação deste projecto muito para além do que era a
sua obrigação.
Desejamos também expressar os nossos agradecimentos ao Sr. Luís Manuel
Jesus da Silva e ao Sr. Manuel Moita Rita, por todo o apoio técnico que nos prestaram e
pelas proveitosas trocas de ideias que tiveram connosco.
Um agradecimento muito especial para as nossas famílias, que tiveram sempre
ao nosso lado nos momentos de maiores dificuldades.
Finalmente, desejamos agradecer à ESTS pelos meios que colocou à nossa
disposição, que tornaram possível a conclusão deste projecto.
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ÍNDICE GERAL
Página
1 – INTRODUÇÃO...........................................................................................................1 1.1 – Descrição do Trabalho..........................................................................................1
1.2 – Organização do Projecto.......................................................................................2
2 – DIAGRAMA DE BLOCOS IMPLEMENTADO .......................................................3 3 – SENSORES .................................................................................................................5
3.1 – Fotodíodo..............................................................................................................5
3.2 – Fototransístor ........................................................................................................7
3.3 – LDR (light dependent resistor) ............................................................................9
3.4 – Disposição dos Sensores.....................................................................................12
3.5 – Opções Tomadas ................................................................................................17
3.5.1 – Três sensores ...............................................................................................17 3.5.2 – Cinco sensores.............................................................................................18 3.5.3 – Quatro sensores ...........................................................................................18
4 – CONTROLO DO SISTEMA ....................................................................................21 4.1 – Controlo ON/OFF...............................................................................................21
5 – ADC...........................................................................................................................23 5.1 MX7828.................................................................................................................23
6 – MOTORES PASSO-A-PASSO.................................................................................24 6.1 – Descrição do Motor Passo-a-Passo ....................................................................24
6.2 – O Meio Passo......................................................................................................24
6.3 – Princípio de Funcionamento ...............................................................................25
7 – DRIVERS ..................................................................................................................29 7.1 – SAA1042 ............................................................................................................29
7.2 – Esquema Eléctrico do Driver..............................................................................30
8 – SISTEMA ARTICULADO .......................................................................................32 9 – COMPORTAMENTO DA CABEÇA EM RELAÇÃO AO ESTÍMULO................35
9.1 – Um Eixo de Cada Vez Contra Dois Eixos em Simultâneo ................................35
9.2 - Descrição do Funcionamento do Sistema ...........................................................37
9.3 - Inicialização do Sistema......................................................................................38
10 – SOFTWARE DE APLICAÇÃO .............................................................................42 11 – TESTES PRÁTICOS...............................................................................................44 12 – APLICAÇÕES ........................................................................................................47 13 – MELHORAMENTOS FUTUROS..........................................................................48 14 – CONCLUSÕES .......................................................................................................49 15 – REFERÊNCIAS BIBLIOGRÁFICAS ....................................................................50
ANEXOS
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ÍNDICE DE FIGURAS
Página
Figura 1.1 – Sistema articulado a controlar. ......................................................................1 Figura 2.1– Diagrama de blocos do sistema implementado. .............................................3 Figura 3. 1 – Configuração básica de polarização.............................................................5 Figura 3. 2 – Corrente inversa em função da luz, retirada da referência [3]. ....................6 Figura 3. 3 – Símbolo do Fotodíodo..................................................................................6 Figura 3. 4 – Curva Característica do Fotodíodo, de [3]. ..................................................7 Figura 3. 5 - Circuito exemplo do fototransístor, de [3]....................................................8 Figura 3. 6 – Símbolo do fototransístor. ............................................................................8 Figura 3. 7 – Curva Característica do fototransístor, de [3]. .............................................9 Figura 3. 8 – Símbolo da LDR. .......................................................................................10 Figura 3. 9 – Medição experimental da variação da tensão aos terminais da LDR em
função da variação da luz ambiente.........................................................................11 Figura 3. 10 – Esquema eléctrico utilizado para medir a variação de luminosidade
apresentada na figura 3.9. ........................................................................................12 Figura 3. 11 – Disposição dos três sensores. ...................................................................13 Figura 3. 12 – Captura de luz. .........................................................................................13 Figura 3. 13 – Situação de luz focada..............................................................................14 Figura 3. 14 – Disposição de quatro sensores no sistema de rotação. .............................14 Figura 3. 15 – A cabeça segue a luz no sentido do sensor que está a captar maior
luminosidade............................................................................................................15 Figura 3. 16 – Situação de luz focada..............................................................................15 Figura 3. 17 – Disposição dos cinco sensores. ................................................................16 Figura 3. 18 – Movimento lateral. ...................................................................................16 Figura 3. 19 – Situação de luz focada..............................................................................17 Figura 3. 20 - Exemplo a com três sensores. ...................................................................17 Figura 3. 21 – Configuração de quatro sensores escolhida. ............................................19 Figura 3. 22 – Protecção da luz lateral. ...........................................................................20 Figura 3. 23 – Luz ambiente em função da luz máxima. ................................................20 Figura 4.1 – Esquema dos sensores em actuação. ...........................................................21 Figura 4. 2 – Resultado do controlo em função da entrada. ............................................22 Figura 5. 1 – Sinais de Controlo do ADC. ......................................................................23 Figura 6. 1 – Configuração de um motor passo-a-passo e disposição do rotor em função
da polaridade da alimentação do estator, retirada de [2]. ........................................26 Figura 6. 2 – Modelo de um motor passo-a-passo com 6 fios.........................................27 Figura 7. 1 – Esquema típico do SAA1042. ....................................................................29 Figura 7. 2 – Esquema eléctrico dos drivers do motor passo-a-passo.............................30 Figura 8. 1 – Sistema de contactos deslizantes................................................................32 Figura 8. 2 – Desmultiplicação de força..........................................................................34
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Figura 9. 1– Caminho percorrido pela cabeça analisando um eixo de cada vez. ............35 Figura 9. 2 – Caminho percorrido pela cabeça analisando os dois eixos em simultâneo.
.................................................................................................................................36 Figura 9. 3 – Placa de circuito impresso do controlo do sistema. ...................................37 Figura 9. 4 – Cabeça na posição inicial (0°)....................................................................38 Figura 9. 5 – Posição limite em elevação (180° ou -180°). .............................................39 Figura 9. 6 – Posição de 45°. ...........................................................................................40 Figura 9. 7 – Posição de -45°...........................................................................................41 Figura 10. 1 – Menu Principal da aplicação desenvolvida. .............................................42 Figura 10. 2 – Gráfico em tempo real dos valores lidos..................................................43 Figura 11. 1 – Gráfico da resposta com um eixo de cada vez. ........................................44 Figura 11. 2 – Gráfico da resposta com os dois eixos em simultâneo.............................45 Figura 11. 3 – Gráfico da resposta do sistema em três situações idênticas. ....................46
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ÍNDICE DE TABELAS
Página
Tabela 6. 1 – Sequência de passos de um motor passo-a-passo......................................28 Tabela 7. 1 – Lista de entradas e saídas do Driver. .........................................................31
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1 – INTRODUÇÃO
1.1 – Descrição do Trabalho
Este projecto tem como finalidade a construção e o controlo de um sistema
articulado semelhante a uma cabeça, i.e., com uma parte fixa (o ombro) e uma parte
móvel com dois graus de liberdade: azimute e elevação (cabeça1), como se pode ver na
figura 1.1, de modo a que a cabeça aponte para a zona que corresponda ao valor
máximo de uma variável, neste caso, a luminosidade.
Figura 1.1 – Sistema articulado a controlar.
Para isso foi desenhado um protótipo com base nos suportes para câmaras de
vídeo em aplicações de vigilância.
A escolha dos sensores, conversor e microcontrolador a utilizar foi uma tarefa
relativamente cuidadosa, pois dos componentes escolhidos dependem muitos factores.
O desenvolvimento do sistema prosseguiu com o estabelecimento do
comportamento da cabeça em função da informação de luminosidade, bem como o
melhoramento global, por via experimental.
Todos os estudos e resultados obtidos durante este projecto podem ainda ser
analisados através da seguinte página: http://ltodi.est.ips.pt/aabreu/cabeca.html.
1 Faltando somente a inclinação para que seja semelhante a uma cabeça
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1.2 – Organização do Projecto
Este projecto encontra-se organizado em 15 capítulos. Assim, neste primeiro
capítulo é feita uma breve introdução do projecto, bem como a forma como este
documento se encontra organizado.
No capítulo 2 é descrito o diagrama de blocos implementado, para se ter uma
melhor visualização dos blocos constituintes do projecto.
No capítulo 3 apresentam-se os tipos de sensores que reagem à luminosidade, e
o porquê da utilização das LDRs. É ainda feito um estudo das possíveis disposições dos
sensores, bem como do número de sensores necessários.
No capítulo 4 é abordada a forma como o sistema é controlado, enquanto que no
capítulo 5 é descrita como é realizada a conversão analógico – digital.
Por outro lado, no capítulo 6 é feito um estudo sobre motores passo-a-passo,
assim como uma caracterização mais pormenorizada dos motores utilizados. No
capítulo 7 é apresentada a forma como foram construídos os drivers para controlar os
motores.
No capítulo 8 são apresentados os factores tidos em conta aquando da realização
do sistema articulado, enquanto que no capítulo 9 é caracterizado o comportamento da
cabeça em relação ao estímulo, bem como a comparação do funcionamento da mesma
quando o controlo incide num eixo de cada vez e nos dois eixos ao mesmo tempo.
No capítulo 10 é mostrado como funciona uma pequena aplicação de
visualização das variáveis do sistema, e no capítulo 11 são feitos os testes práticos do
comportamento da cabeça em relação a vários estímulos, utilizando para tal o software
de aplicação.
No capítulo 12 apresentam-se algumas aplicações deste projecto, enquanto que
no capítulo 13 apontam-se alguns melhoramentos possíveis.
Por fim nos capítulos 14 e 15 são apresentadas as conclusões de projecto, bem
como algumas referências bibliográficas.
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2 – DIAGRAMA DE BLOCOS IMPLEMENTADO O diagrama apresentado na figura 2.1 específica todos os blocos constituintes do projecto, assim como as ligações entre cada um deles.
Figura 2.1– Diagrama de blocos do sistema implementado.
O bloco “Sensores” diz respeito ao conjunto de Sensores, tendo como função
captar a luminosidade ambiente. Esta luminosidade que é enviada para o bloco “ADC”,
sob a forma de tensão.
O bloco “ADC” é constituído por uma conversor analógico/digital que recebe os
valores provenientes do bloco “Sensores”. Sempre que o bloco “Microcontrolador” o
entenda, o “ADC” converte os valores, e envia-os para o mesmo, para que possam ser
processados.
O bloco “Microcontrolador” controla ainda 2 drivers, para os motores. Este
bloco, sempre que necessário, faz um pedido ao bloco “ADC” para que este converta os
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valores dos sensores, e depois de processar a informação, envia as ordens de comando
para o bloco “Motores”, através dos drivers.
O bloco “Motores” é constituído por dois motores passo-a-passo, e tem como
única função provocar o movimento do sistema articulado, para que este siga o foco de
luz.
Após esta breve introdução, é apresentado um estudo mais aprofundado de como
estes blocos interagem entre si, assim como a sua constituição.
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3 – SENSORES
Para a escolha dos sensores de luminosidade a utilizar foi realizado um estudo
sobre três tipos de sensores: fotodíodos, fototransístores e LDRs2.
3.1 – Fotodíodo
É um dispositivo semicondutor de junção P-N, construído de forma especial, de
modo a possibilitar a utilização da luz como factor determinante no controlo de corrente
eléctrica. A sua configuração básica de polarização é apresentada na figura 3.1. De notar
que este se encontra polarizado inversamente.
A aplicação de luz na junção P-N provoca uma transferência de energia das
ondas de luz incidentes (na forma de fotões) para a estrutura atómica, aumentando com
isto, o número de portadores minoritários e consequentemente o nível de corrente
inversa.
Uma vantagem importante neste dispositivo é o de a corrente inversa variar
proporcionalmente com a luminosidade, como se pode constatar na figura 3.2.
Figura 3. 1 – Configuração básica de polarização.
2 Resistência dependente da luz
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Figura 3. 2 – Corrente inversa em função da luz, retirada da referência [3].
Símbolo:
Figura 3. 3 – Símbolo do Fotodíodo.
Constituição física:
É composto por duas pastilhas de silício como num díodo semicondutor normal.
A diferença está no tamanho das pastilhas que são maiores que a dos díodos
convencionais, além de existir uma “janela”, que possibilita a incidência dos raios
luminosos na junção.
Características:
• Corrente inversa e o fluxo luminoso possuem relação quase linear.
• Resposta (velocidade) é muito mais rápida que a LDR.
• Sensível a luz visível, infravermelho e ultravioleta.
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Curva Característica:
Figura 3. 4 – Curva Característica do Fotodíodo, de [3].
Aplicações:
• Medir a intensidade luminosa (fotografia);
• Detecção de sinais luminosos de alta- frequência.
3.2 – Fototransístor
O fototransístor é um dispositivo que funciona baseado no fenómeno da
fotocondutividade. Como nas outras células fotocondutoras, a incidência de luz (fotões)
provoca o surgimento de buracos na vizinhança da junção base-colector. Esta tensão faz
com que os buracos se “movam” para o emissor, enquanto os electrões passam do
emissor para a base. Isto provocará um aumento da corrente de base, o que por
consequência implicará um aumento da corrente de colector ß vezes (Ic = ß . IB), sendo
este aumento proporcional à intensidade de luz incidente.
Como a base está normalmente desligada, a corrente que circula por ela
dependerá apenas da luz incidente. Assim, na ausência de luz, a corrente de base será
zero e o fototransístor está ao corte, resultando na tensão do colector igual à tensão de
polarização Vcc, como se ilustra na figura 3.5. Quando há luz incidindo sobre o
fototransístor, a tensão no colector irá diminuir devido ao aumento da corrente.
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Na escolha de um fototransístor para uma dada aplicação, precisamos de
observar a sua sensibilidade à frequência da radiação utilizada (tipo de luz), a corrente
que ele fornece e a tensão máxima que pode ser aplicada entre o colector e o emissor.
Figura 3. 5 - Circuito exemplo do fototransístor, de [3].
Símbolo:
Figura 3. 6 – Símbolo do fototransístor.
Ligação:
O terminal de base poderá ou não estar electricamente ligado. Nas aplicações
normais, os fototransístores são utilizados com a base livre (NC). A corrente que circula
entre o colector e o emissor depende da luz e é então aproveitada para controlo de um
circuito.
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Curva Característica:
Figura 3. 7 – Curva Característica do fototransístor, de [3].
Aplicações:
• Equipamentos de controlo de luz
• Leitura de cartões
• Acopladores ópticos
3.3 – LDR (light dependent resistor)
Existem substâncias que alteram a sua resistência em função da quantidade de
luz que recebem. Os fotões de luz visível que a substância recebe retiram os electrões
das órbitas, aumentando assim o número de electrões livres e facilitando a condução de
corrente.
O sulfato de cádmio (Cds) é uma das substâncias utilizadas para o fabrico de
Ldrs.
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Símbolo:
Figura 3. 8 – Símbolo da LDR.
Características:
• Não são componentes polarizados.
• Dissipam calor como as resistências.
• A capacidade é directamente proporcional à área de sensibilidade, ou seja,
quanto maior for a superfície de incidência da luz, mais sensível é a LDR, e por
outro lado possibilita o controlo de correntes mais intensas por parte desta.
• A resistência da LDR varia com a luz do seguinte modo: 1MΩ<R(ambiente
escuro)<10MΩ e 75Ω<R(ambiente iluminado)< 500Ω
• Resposta espectral:
o A sensibilidade da LDR é maior para comprimentos de onda que
reproduzem a cor vermelha, tendendo um pouco para a laranja (6800
Angstron);
o É sensível a comprimentos de onda que o olho humano não percebe,
como o infravermelho (7000 a 7500 Angstron)
• Resposta de actuação:
o A LDR é um dispositivo lento. Estando todo iluminado, aquando da
retirada da fonte de luz e em comparação com o fotodíodo/fototransístor,
denota-se uma demora até que a sua resistência volte ao valor máximo.
Assim sendo, a sua aplicação não é viável, por exemplo, em leitura de código de
barras. No entanto, pode aplicar-se em brinquedos, detectores de nível de iluminação,
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sensores de luz ambiente, etc., visto não ser necessária uma verificação rápida da
variação da resistência com a luz.
Portanto, após um estudo teórico e alguns testes experimentais, o sensor
escolhido para leitura da quantidade de luz foi a LDR.
As razões principais da desta escolha têm por base as seguintes características
das LDR: são sensores que têm um tempo de resposta aceitável à detecção de luz, na
ordem dos 33ms, como se pode ver na figura 3.9; e não variam de uma forma brusca
com a variação de luz, ao contrário dos fotodíodos e dos fototransístores.
Figura 3. 9 – Medição experimental da variação da tensão aos terminais da LDR em função da variação da luz ambiente.
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Para se chegar ao resultado da figura foi implementado o circuito da figura 3.10.
Figura 3. 10 – Esquema eléctrico utilizado para medir a variação de luminosidade apresentada na figura 3.9.
Este funciona como um divisor de tensão, em que a tensão de saída varia
directamente com a variação da resistência na LDR.
ViLDRR
RVo
+=
11
3.4 – Disposição dos Sensores
O número mínimo de sensores para que a cabeça consiga seguir um foco de luz,
num espaço a 2 dimensões3, é três, com a disposição apresentada na figura 3.11.
Contudo, esta opção introduz uma maior complexidade ao nível do controlo, pois não se
pode associar a cada sensor uma direcção.
3 Azimu te – θ , Elevação – ϕ
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Figura 3. 11 – Disposição dos três sensores.
Quando é detectada luz pelo grupo de sensores, a informação é processada
resultando um movimento composto, i.e., movimento nos 2 eixos, tal como se ilustra na
figura 3.12. Relativamente a essa figura há que referir que a cor dos círculos representa
a luminosidade que cada sensor recebe, ou seja, quanto mais claro for círculo, maior
luminosidade está a receber o sensor.
Figura 3. 12 – Captura de luz.
Nesta disposição considera-se que a cabeça está a apontar para o foco de luz
quando todos os sensores medirem a mesma luminosidade, tal como se ilustra na figura
3.13.
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Figura 3. 13 – Situação de luz focada.
Por outro lado, a utilização de 4 sensores permite associar os dois sentidos dos
dois eixos de rotação (ϕ e θ ) a cada sensor, de acordo com o ilustrado na figura 3.14.
Figura 3. 14 – Disposição de quatro sensores no sistema de rotação.
Para o seguimento do foco de luz, os sensores são analisados dois a dois,
avaliando-se os semi-eixos em que os movimentos devem ser feitos. Por exemplo, a
diferença entre os sensores de topo e de baixo, permite determinar qual o sentido de
movimento a realizar no eixo ϕ .
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Figura 3. 15 – A cabeça segue a luz no sentido do sensor que está a captar maior luminosidade.
Para se poder dizer que a posição do foco de luz está devidamente determinada,
todos os sensores devem receber a mesma intensidade de luz, ver figura 3.16.
Figura 3. 16 – Situação de luz focada.
No caso de serem utilizados cinco sensores, a disposição a realizar seria a que se
apresenta na figura 3.17.
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Figura 3. 17 – Disposição dos cinco sensores.
Os quatro sensores dispostos em quadrado correspondem a cada uma das
direcções possíveis de movimento, tal como no caso anterior. O sensor que captar maior
luminosidade determina qual o sentido e direcção em que a cabeça se deve mover (ver
figura 3.18).
Figura 3. 18 – Movimento lateral.
Neste caso, o sensor do meio permitiria o reconhecimento da cabeça focada, ou
seja, quando o sensor do meio apresenta o maior valor, então a cabeça está focada (ver
figura 3.19).
O quinto sensor, como se verá, para além de ser redundante piora o desempenho
do sistema, como tal é dispensado.
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Figura 3. 19 – Situação de luz focada.
3.5 – Opções Tomadas
3.5.1 – Três sensores
Como já foi referido, o uso de três sensores complica o processo de controlo do
sistema, assim apesar de não ter sido testado na prática foi realizado o seguinte estudo
teórico:
Considere-se a seguinte situação:
Figura 3. 20 - Exemplo a com três sensores.
O movimento deve ser proporcional a:
→−=−→=−
ϕφ
eixonoseneixono
5,0)30(89,0)30cos(
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Agora, há que transformar 0,89 e -0,5 em quantidades inteiras. Primeiro vai-se
convencionar que basta trabalhar com uma casa decimal.
Seja:
5,0|)5,0||;87,0min(| =−=m
15,05.05.0
;74,15,087,087,0
====mm
Como é que se anda 1,74 unidades no eixo ? e 1 no eixo ϕ ? Tem que se definir
a precisão que se quer. Para isso pode-se definir os seguintes pares de movimento: (1,1),
(2,3), (3,5), (4,7); Caso se continuasse obter-se- ia uma maior precisão, mas o
movimento seria maior. O movimento (3,5) talvez seja um bom ponto de equilíbrio.
3.5.2 – Cinco sensores
Foi inicialmente testado o funcionamento da cabeça com cinco sensores.
Contudo chegou-se à conclusão de que esta disposição tinha o inconveniente de não
reagir a pequenos movimentos do foco, ou seja, enquanto o sensor do meio retornar o
maior valor, a cabeça não se mexe, pois é considerada focada podendo esse sensor
captar mais luminosidade.
3.5.3 – Quatro sensores
Assim, e para eliminar os problemas surgidos nas configurações já apresentadas,
a escolha recaiu na configuração com quatro sensores, como se pode ver na figura 3.20.
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.
Figura 3. 21 – Configuração de quatro sensores escolhida.
Foi também colocada a hipótese da utilização de um sensor na parte traseira da
cabeça, para apanhar fontes de luz que aparecessem na posição diametralmente oposta à
dos sensores (i.e., na nuca). Esta opção apresenta a desvantagem de necessitar de mais 1
sensor. Com efeito quando passa algum tempo sem que a cabeça capte luz que não seja
a ambiente, esta executa uma procura sistemática, prescutando todo o espaço
envolvente.
Outra opção tomada relativamente aos sensores teve a ver com o ângulo de
captura das LDR, que é muito grande. Para isso foram colocadas umas protecções em
todos os sensores, tal como se apresenta na figura 3.21, para que a luz vinda
lateralmente não seja captada. Deste modo, cada sensor indica a presença de fontes de
luz que estejam na direcção do seu eixo longitudinal.
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Figura 3. 22 – Protecção da luz lateral.
Uma das contrariedades na realização do trabalho foi a existência de luz
ambiente forte. Quando a luz ambiente é muito forte, é necessário que o foco de luz seja
ainda mais forte para que seja reconhecido como tal. Para além disso, quanto mais perto
o nível da luz ambiente estiver do nível de saturação da LDR, mais difícil, se não
mesmo impossível, é a detecção e seguimento do foco (ver figura 3.22).
Figura 3. 23 – Luz ambiente em função da luz máxima.
Portanto temos:
O domínio da variável luminosidade captada pelo sensor, que se determina
subtraindo o nível de luz ambiente da luz máxima captada, deve ser tão grande quanto
possível, isto é, a luz ambiente deve ser baixa e o foco deve emitir luz forte.
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4 – CONTROLO DO SISTEMA
4.1 – Controlo ON/OFF
Para o controlo do sistema em causa foi utilizado um controlo ON/OFF, ou seja,
são lidos os valores provenientes dos sensores (figura 4.1), e é feita uma subtracção. Se
o valor da subtracção for superior a um dado valor (Sensibilidade), então o motor que
comanda a elevação move-se um passo (ON) no sentido indicado pelo sinal da
subtracção. Caso contrário, o sistema não mexe (OFF). O valor de sensibilidade é
ajustado experimentalmente.
Figura 4.1 – Esquema dos sensores em actuação.
Com vista a resumir o texto, só se faz a explicação do cálculo do movimento
para o eixo ϕ , ou seja, só se considera os sensores 1 e 2, de acordo com a figura 4.1. Os
cálculos para o restante eixo são semelhantes.
Considere-se que:
21 SensorSensorS −=∆
E que o comportamento do sistema é dado por:
⇒≥∆⇒<∆
ONadeSensibilidSOFFadeSensibilidS
O que controla o sentido de rotação, cima ou baixo, é o sinal de S∆ .
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Assim:
BaixoSCimaS
⇒>∆⇒<∆
00
Como conclusão pode dizer-se que:
Figura 4. 2 – Resultado do controlo em função da entrada.
−⇒∧⇒∧
⇒
=1
1
0
BaixoONCimaON
OFF
resposta
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5 – ADC
5.1 MX7828
Para transformar os valores de tensão provenientes das LDR em informação
digital, é necessária a utilização de um conversor analógico para digital.
Assim e após um estudo de mercado, foi escolhido o ADC MX7828, cujo
datasheet se encontra no anexo A.3, dado ter uma velocidade de conversão elevada, na
ordem dos 2,5µs por canal, e por ter 8 canais, o que é importante quando se usam
muitos sensores. É um ADC de 8 bits com interface paralelo.
Este ADC possui 4 sinais de controlo para fazer-se a conversão de analógico
para digital: o /CS (chip-select), /RD (read), RDY (ready) e /INT (interrupt output).
Como se pode comprovar pela figura 4.1, todos os sinais são inicialmente
colocados a 1, em seguida são colocados a 0 os sinais /CS, /RD pelo micro, e RDY e
/INT pelo ADC. A informação convertida fica disponível nos pinos correspondentes.
Por último, e para se poder realizar mais uma conversão, os sinais /RD, /INT, RDY e
/CS são colocados a 1.
O intervalo de tempo entre as activações de /CS e /RD não é tomado em
consideração porque é muito pequeno, o que é garantido pelo tempo que demoram as
instruções do microcontrolador.
Figura 5. 1 – Sinais de Controlo do ADC.
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6 – MOTORES PASSO-A-PASSO
6.1 – Descrição do Motor Passo-a-Passo
Num motor passo-a-passo, como o próprio nome indica, o veio move-se uma
quantidade discreta, denominada passo, em resposta à aplicação de um sinal eléctrico
entre dois dos seus terminais. A velocidade com que o veio se move é função da taxa a
que se sucedem os passos. Assim, um motor passo-a-passo é um dispositivo síncrono.
Enquanto a diferença de potencial estiver aplicada nesses terminais, o veio do motor
está parado, fazendo uma força que se opõe a qualquer movimento imposto
exteriormente. Por outro lado, quando se remove a tensão entre os dois terminais, o veio
fica livre, deixando de fazer essa força, pelo que passa a ser fácil rodar o veio.
Um motor passo-a-passo dispõe no seu interior de diversos enrolamentos ou
bobinas. A quantidade de movimento angular num motor passo-a-passo ou o tamanho
do passo, é fixa e depende da configuração dos enrolamentos existentes. Nos dois
motores passo-a-passo utilizados no projecto, o que controla o azimute tem um passo de
4,5° e o que controla a elevação tem um passo de 1,82°. Em azimute são necessários
198 passos para se dar uma volta completa, enquanto que no eixo da elevação o motor
apenas necessita de dar 80 passos.
Azimute
passo/5,480360 °=÷
Elevação
passo/82,1198360 °=÷
6.2 – O Meio Passo
O meio passo é conseguindo alimentando um enrolamento de cada vez em
alternância com a alimentação de ambos os enrolamentos. O meio passo tem o
inconveniente de que, por um lado tem-se que o torque varia de meio passo em meio
passo, dado que numas posições é alimentado um enrolamento e nas restantes são
alimentados dois enrolamentos, o que faz com que a força realizada não seja sempre a
mesma, mas por outro lado o meio passo tem a vantagem de permitir um controlo mais
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fino, e, como tal, mais preciso. Como o principal objectivo do projecto é a precisão na
posição e não a força, decidiu-se utilizar o meio passo.
6.3 – Princípio de Funcionamento
Um motor é constituído por um rotor, que é a parte móvel, e por um estator, que
é a parte fixa. O veio do motor está acoplado ao rotor. A figura 6.1 a) pode ser
entendida como uma aproximação ao interior de um motor passo-a-passo.
Considere-se um motor com dois enrolamentos. Logo que seja aplicada uma
diferença de potencial aos terminais do motor, segundo a polaridade indicada na figura
6.1 b) e cuja grandeza não é importante, a passagem da corrente eléctrica cria nas
bobinas um campo magnético cuja polaridade é também apresentada na figura 6.1 b).
Dado que pólos diferentes atraem-se, então o veio do motor é levado para a posição
indicada, que é a única onde a distância entre os pólos opostos do rotor e do estator é
menor neste caso. Se a polaridade aos terminais do motor for invertida, como
evidenciado na figura 6.1 c), então o veio roda em sentido contrário ao da figura 6.1 b),
pois pólos iguais repelem-se. Contudo, após a rotação do rotor, essa força vai-se
transformar em força de atracção.
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Figura 6. 1 – Configuração de um motor passo-a-passo e disposição do rotor em função da polaridade da alimentação do estator, retirada de [2].
Existem vários tipos de motores passo-a-passo. Relativamente à constituição do
rotor, existem motores de relutância variável e de magneto permanente. Quanto à
configuração interna, existem os unipolares e os bipolares.
Os motores utilizados no projecto são motores passo-a-passo unipolares com
cinco fios, apresentando uma configuração idêntica à da figura 6.2; contudo, os
terminais Power1 e Power2 estão ligados interiormente entre si, ao contrário do que
acontece nos motores com seis fios.
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Figura 6. 2 – Modelo de um motor passo-a-passo com 6 fios.
Os motores passo-a-passo podem funcionar em passo simples, em passo simples
com duas fases e em meio passo como se ilustra na tabela 6.1.
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Tabela de sequência de passos
Sequência
1a 2b 1b 2a Nome Descrição
0 0 0 1
0 0 1 0
0 1 0 0
1 0 0 0
Passo Simples
Cada enrolamento é alimentado de
cada vez, conseguindo-se um
menor consumo de corrente.
0 0 1 1
0 1 1 0
1 1 0 0
1 0 0 1
Passo Simples
com
Duas Fases
Os enrolamentos são alimentados
dois a dois, daí o nome “Duas
Fases”. Assim temos um
comportamento igual ao passo
simples, mas com mais força. O
consumo de corrente é maior
0 0 0 1
0 0 1 1
0 0 1 0
0 1 1 0
0 1 0 0
1 1 0 0
1 0 0 0
1 0 0 1
Meio Passo
Funciona a partir das duas formas
anteriores, e obtêm-se uma
precisão maior. É de notar que a
sequência é constituída por oito
passos.
Tabela 6. 1 – Sequência de passos de um motor passo-a-passo.
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7 – DRIVERS
7.1 – SAA1042
O SAA1042 é um driver para motores passo-a-passo. Este circuito integrado
possui 3 estados de entrada, 2 estados de saída e uma secção de lógica; suporta até
500mA, funciona com comandos CW/CCW, com meio passo ou passo completo.
Para isso foi utilizado o CI SAA1042, (ver anexo A.4) de forma a permitir um
controlo de direcção e velocidade com apenas dois pinos para cada motor (Clock e
CW/CCW), ver figura 7.1. A sua utilização é vantajosa se tivermos em consideração o
número de portos disponíveis pelo microcontrolador AT89C51 (ver anexo A.1), caso
contrário eram necessários 8 pinos.
Figura 7. 1 – Es quema típico do SAA1042.
Outra vantagem prende-se com o facto de se trabalhar em meio passo, o que
aumenta a precisão em 100%. Contudo, este CI é limitado ao nível da corrente
disponibilizada para o motor. Assim fo i utilizado um circuito simples com transístores
de potência, de modo a permitir maiores consumos no motor a partir da fonte de
alimentação. Neste caso, o sinal gerado pelo CI é apenas de controlo.
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Um problema que se coloca é devido à elevada corrente que o motor necessita
para trabalhar correctamente, na ordem de 1A/1,5A. O regulador normalmente utilizado,
e facilmente adquirível no mercado, é o 7805C, cujo datasheet se encontra no anexo
A.5, que suporta uma corrente máxima de 1,2A. Na impossibilidade prática de se
encontrar outra solução optou-se pelo uso de dois desses reguladores em paralelo, sendo
necessário proceder à escolha de dois reguladores o mais iguais entre si, de uma forma
experimental, para que a distribuição da corrente pelos dois fosse semelhante.
Devido aos valores de corrente que percorrem os reguladores serem muito
próximos do valor máximo, optou-se por se utilizar dissipadores como forma de facilitar
a dissipação do calor gerado por efeito de Joule e assim aumentar o seu tempo de vida.
7.2 – Esquema Eléctrico do Driver
Figura 7. 2 – Esquema eléctrico dos drivers do motor passo-a-passo.
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A tabela 7.1 mostra a lista de entradas e saídas do esquema da figura 7.2.
Tabela de Entradas/Saídas
Pino Nome Descrição
U9.1 GND Massa do sistema.
U9.2 +5V +5 Volt, sai directamente dos reguladores para
alimentar o motor.
U9.3 VI Alimentação do sistema.
U10.1 Dir_x Sinal proveniente do microcontrolador que
define a direcção de rotação.
U10.2 Freq_x Sinal proveniente do microcontrolador que
controla a velocidade de rotação.
U10.3 L4
Enrolamento do motor. Quando o transístor Q8
recebe um sinal do SAA1042, este pino fica
ligado á massa.
U11.1 L3
Enrolamento do motor. Quando o transístor Q7
recebe um sinal do SAA1042, este pino fica
ligado á massa.
U11.2 L2
Enrolamento do motor. Quando o transístor Q5
recebe um sinal do SAA1042, este pino fica
ligado á massa.
U11.3 L1
Enrolamento do motor. Quando o transístor Q6
recebe um sinal do SAA1042, este pino fica
ligado á massa.
Tabela 7. 1 – Lista de entradas e saídas do Driver.
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8 – SISTEMA ARTICULADO
O suporte utilizado para dar forma à cabeça foi desenhado tendo em conta os
suportes para vídeo vigilância, ver desenho no anexo G.
O tamanho deste foi bastante influenciado pelo tamanho dos motores passo-a-
passo disponíveis.
Um dos factores que foi tido em conta no projecto do suporte foi não haver
limitação na rotação da cabeça em azimute. Para isso foi utilizado um sistema de
transmissão da alimentação eléctrica através de contactos deslizantes (ver anexo C.3),
como se ilustra na figura 8.1.
Figura 8. 1 – Sistema de contactos deslizantes.
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São utilizados contactos em cobre que apresentam uma resistência muito
pequena, praticamente nula, quando comparados com escovas de carvão, como chegou
a ser testado. Estas últimas possuíam uma resistência de 30O em repouso e em
movimento chegavam a valores na ordem dos 400O a 1KO, considerados inviáveis. A
sua utilização requeria que a fonte de alimentação debitasse uma tensão na ordem dos
10 a 11 Volt. Por outro lado, tinha-se o inconveniente de que a tensão que alimentava o
circuito não era estável, mas oscilante entre 3,5 e 5 Volt, consoante a resistência da
escova de carvão nessa altura.
Como os motores passo-a-passo utilizados não são iguais, necessitam de um
número diferente de passos para percorrerem 360º (198 passos em elevação e 80 passos
em azimute). Assim, foi implementado um sistema de desmultiplicação de forças
usando dois carretos de dimensões diferentes unidos por uma correia, para que o
número de passos em elevação fosse mais ou menos o mesmo que em azimute, como se
pode ver na figura 8.2.
Tendo o carreto acoplado ao motor um diâmetro de 41 milímetros e o do eixo 16
milímetros consegue-se um factor multiplicativo (F_Mul) de:
39,04116
_ ==MulF
O que aplicado ao número de passos necessários passa a ser:
7739,0198 ≈×=Passos
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Figura 8. 2 – Desmultiplicação de força.
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9 – COMPORTAMENTO DA CABEÇA EM RELAÇÃO AO ESTÍMULO
Para controlar a cabeça em resposta à luz foi utilizado o microcontrolador
AT89C51, cujo datasheet se encontra no anexo A.1. Este microcontrolador tem
internamente 4 Kbytes de memória flash, 128*8 Bytes de RAM interna, 32 linhas de
Entrada/Saída programáveis e 2 contadores de 16 bits.
9.1 – Um Eixo de Cada Vez Contra Dois Eixos em Simultâneo
A operação de seguimento da luz por parte da cabeça, não é uma operação muito
complexa, tendo sido pensada de modo a ser a mais precisa e rápida possível.
Inicialmente utilizou-se uma forma de controlo que trabalha um eixo de cada
vez, (ver figura 9.1), ou seja, só depois de alinhar em elevação e que se passa para o
alinhamento em azimute.
Caminho Percorrido
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Elevação - Nº Passos
Azi
mu
te -
Nº
Pas
sos
Caminho 1
Figura 9. 1– Caminho percorrido pela cabeça analisando um eixo de cada vez.
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Esta abordagem apresenta 2 defeitos:
– O tempo total para o alinhamento corresponde à soma dos tempos para o
alinhamento em cada eixo.
– Quando está a alinhar em elevação não capta movimentos em azimute
Para eliminar estes defeitos, foi utilizado outro método, alinhando-se os 2 eixos
em simultâneo (ver figura 9.2).
Caminho Percorrido
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Elevação - Nº Passos
Azi
mu
te -
Nº
Pas
sos
Caminho2
Figura 9. 2 – Caminho percorrido pela cabeça analisando os dois eixos em simultâneo.
Resultados:
– Diminuição do tempo de focagem.
– Capta todos os movimentos do foco em todos os instantes.
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9.2 - Descrição do Funcionamento do Sistema
O controlo da cabeça com base nos pares de sensores cima/baixo e
esquerda/direita, separadamente, é do tio ON/OFF. Assim, o microcontrolador recebe os
valores dos sensores através do ADC e realiza as subtracções como está descrito no
capítulo CONTROLO DO SISTEMA. Depois de realizada esta operação o
microcontrolador provoca o movimento dos motores, ficando o foco mais perto do
centro dos sensores. Para isso foi implementado o circuito eléctrico apresentado no
anexo B.2, assim como a respectiva placa de circuito impresso (ver anexo C.2), como se
ilustra na figura 9.3.
Figura 9. 3 – Placa de circuito impresso do controlo do sistema.
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9.3 - Inicialização do Sistema
Sempre que o sistema é ligado é necessário que o grupo de sensores esteja
virado para cima (posição inicial - 0°, ver figura 9.4), para que o sistema possa saber a
posição exacta da cabeça a qualquer instante. Este aspecto é importante, pois só assim
se pode limitar a rotação em elevação, entre 180° e -180°, na figura 9.5 apresenta-se a
cabeça com orientação -180°. Caso a cabeça continuasse a rodar, o conjunto de fios que
se vê do lado esquerdo enrolar-se- iam em torno do eixo metálico.
É também importante saber a posição da cabeça por causa dos sensores que
controlam o azimute, o sentido que estes comandam deve ser trocado quando se passa
de um ângulo positivo para um negativo. Caso esta troca não aconteça, verifica-se que a
cabeça tem um comportamento normal quando está a trabalhar em ângulos positivos,
mas quando entra nos ângulos negativos, em vez de seguir a luz, afasta-se dela, no eixo
da azimute.
Figura 9. 4 – Cabeça na posição inicial (0°).
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Figura 9. 5 – Posição limite em elevação (180° ou -180°).
Após os sensores estarem na posição de 0°, e o sistema ter sido inicializado,
inicia-se o reconhecimento da quantidade de luz ambiente. Este reconhecimento
acontece da seguinte forma: a cabeça desloca-se 45° em elevação, como se ilustra na
figura 9.6, em seguida dá uma volta de 360° em azimute, e depois volta à posição 0° em
elevação, durante estes movimentos, os valores dos sensores são guardados, o valor
mais elevado é considerado o valor de luz ambiente.
Só depois de o sistema ter realizado este reconhecimento da quantidade de luz
ambiente é que se pode dizer que a cabeça está em condições de seguir um foco de luz.
No caso de o sistema não detectar um foco de luz num período de 10 segundos, é
realizada uma pesquisa com vista à procurar fontes de luz que possam ter surgido na
zona de sombra dos sensores. Antes de a executar, a cabeça é colocada na posição 45°
(ver figura 9.6) ou -45° (ver figura 9.7), dependendo se esta se encontra no lado positivo
ou no lado negativo do eixo da elevação. Esta pesquisa consiste numa rotação de 360°
em azimute, durante a qual os valores dos sensores e respectiva posição são guardados.
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Assim que a volta de pesquisa acabe, a cabeça, caso tenha encontrado alguma
luminosidade maior, desloca-se para o local onde essa se encontra.
Figura 9. 6 – Posição de 45°.
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Figura 9. 7 – Posição de -45°.
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10 – SOFTWARE DE APLICAÇÃO
Tendo em vista o controlo da cabeça através de um computador, ou apenas para
uma melhor visualização das variáveis envolvidas no processo, foi desenvolvida uma
aplicação em Visual Basic, cujo o código se apresenta no anexo E.
Esta aplicação é constituída basicamente por duas janelas apresentadas nas
figuras 10.1 e 10.2. A primeira permite iniciar e parar o processo, alterar valores de
referência, sensibilidade e visualizar os valores provenientes dos sensores. A outra tem
como única função permitir ao utilizador a visualização de um gráfico em tempo real e a
informação do desvio da cabeça em relação ao ponto de maior luminosidade.
Figura 10. 1 – Menu Principal da aplicação desenvolvida.
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Figura 10. 2 – Gráfico em tempo real dos valores lidos.
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11 – TESTES PRÁTICOS
Foram realizados alguns testes de forma a se poder avaliar o comportamento da
cabeça em função da luz recebida.
O primeiro teste é relativo ao tempo necessário para que a cabeça ficasse focada.
A figura 11.1, é relativa à estabilização de um eixo de cada vez ao passo que a figura
11.2 é relativa à estabilização dos dois eixos em simultâneo.
Constata-se que, como previamente mencionado, o sistema com estabilização
em dois eixos em simultâneo é mais eficiente.
Captura de Luz
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70
Amostra
Dif
eren
ça d
a L
uz
Vertival
Horizontal
Figura 11. 1 – Gráfico da resposta com um eixo de cada vez.
Na figura 11.1 pode-se ver que o número de amostras necessário para que a luz
se considere focada é aproximadamente 45, sendo necessárias cerca de 15 para
estabilização no eixo ϕ e 30 para estabilização no eixo ?. Tendo-se 20 amostras por
segundo, pode-se dizer que o sistema demora 2,25s a orientar-se para a luz.
Escola Superior de Tecnologia de Setúbal Projecto Final de Curso
Instituto Politécnico de Setúbal 45
Captura de Luz
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
30
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70
Amostra
Dife
renç
a da
Luz
Elevação
Azimute
Figura 11. 2 – Gráfico da resposta com os dois eixos em simultâneo.
Na figura 11.2 pode-se ver que o número de amostras necessário para que a luz
se considere focada é aproximadamente 27. Tal como anteriormente, assumindo 20
amostras por segundo, verifica-se que são necessários 1,4s para se obter a focagem.
A experiência cujo o resultado se apresenta na figura 11.2 foi repetida diversas
vezes, para verificar se a cabeça tinha sempre o mesmo comportamento. Partindo
sempre do mesmo sítio e respondendo a um estímulo que se encontrava sempre no
mesmo lugar, verificou-se que a cabeça tem sempre o mesmo comportamento (ver
figura 11.3).
Escola Superior de Tecnologia de Setúbal Projecto Final de Curso
Instituto Politécnico de Setúbal 46
Captura de Luz
-25
-20
-15
-10
-5
0
5
10
15
20
25
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70
Amostra
Dife
renç
a da
Luz
Elevação1
Azimute1
Elevação2
Azimute2
Elevação3
Azimute3
Figura 11. 3 – Gráfico da resposta do sistema em três situações idênticas.
Escola Superior de Tecnologia de Setúbal Projecto Final de Curso
Instituto Politécnico de Setúbal 47
12 – APLICAÇÕES
O sistema desenvolvido pode ser aplicado em algumas situações práticas.
Pode-se utilizar em células fotovoltaicas ou painéis de aquecimento de água,
com orientação solar e assim ter-se um maior aproveitamento da energia solar.
Em sistemas de vigilância, trocando o tipo de sensores a utilizar para sensores
PIR, pode-se aplicar em sistemas de detecção e seguimento de pessoas.
Escola Superior de Tecnologia de Setúbal Projecto Final de Curso
Instituto Politécnico de Setúbal 48
13 – MELHORAMENTOS FUTUROS
Um dos aspectos que podem ser melhorados diz respeito ao valor de referência.
Com efeito, quando a cabeça começa a funcionar realiza uma volta para determinar a
luminosidade ambiente; a partir daí este valor permanece inalterado. Passa-se a ter um
problema pois a luz ambiente varia bastante durante o dia. Analise-se o seguinte caso: a
cabeça começa a funcionar às 9h numa sala de aula com três janelas viradas para o
nascente. O valor de referência obtido é 214. Passada uma hora foi notado que a cabeça
não respondia apenas ao foco de luz mas também respondia à luz exterior.
Uma das possibilidades para a resolução deste problema é fazer-se uma pesquisa
automática que procura o local de maior luminosidade. Caso este valor seja maior que a
referência, esta é actualizada por este valor. É assim conseguida uma referência
dinâmica ao longo do tempo.
È também possível a utilização de mais sensores pois existem disponíveis oito
canais de conversão analógico/digital.
Um melhoramento interessante está na remoção da limitação de rotação no eixo
de elevação.
Escola Superior de Tecnologia de Setúbal Projecto Final de Curso
Instituto Politécnico de Setúbal 49
14 – CONCLUSÕES
Este trabalho permitiu conhecer o funcionamento dos sensores de luz existentes
no mercado. Foi escolhida a LDR pois o seu comportamento é muito bom para o tipo de
sistema desenvolvido, pois, apesar de se considerar lento em relação a outros estudados
tem uma gama de variação maior.
Inicialmente o trabalho foi realizado com a utilização de cinco sensores, contudo
e após a realização de alguns testes, foi notada claramente a vantagem de se trabalhar
com quatro sensores pois conseguia-se “apanhar” muito melhor pequenos movimentos
do foco de luz.
A luz ambiente foi um dos factores que influenciou o desempenho do sistema.
Com efeito, a sua intensidade varia de local para local, assim como de hora para hora.
No que diz respeito aos motores passo-a-passo foi aproveitada a possibilidade da
utilização do meio passo para aumentar a precisão da cabeça. Outro factor que teve de
ser levado em consideração foi a velocidade máxima de funcionamento dos motores.
O facto de o sistema poder rodar em azimute sem constrangimentos, recorrendo
a contactos deslizantes, é uma característica positiva do trabalho. Foram testadas
escovas de carvão e de cobre, tendo-se observado os efeitos produzidos pelo movimento
na condutividade do carvão (aumento da resistência). As escovas de cobre apresentam
um bom contacto eléctrico, mas o atrito pode provocar desaparecimento das pistas no
longo prazo.
Foram testados dois métodos de seguimento da luz: alinhando um eixo de cada
vez e alinhando os dois eixos em simultâneo. Apesar de os dois serem eficazes o
segundo é superior, daí a escolha ter recaído sobre este.
Escola Superior de Tecnologia de Setúbal Projecto Final de Curso
Instituto Politécnico de Setúbal 50
15 – REFERÊNCIAS BIBLIOGRÁFICAS [1] A série MCS51 de Microcontroladores de oito bits da Intel, António Abreu,
Escola Superior de Tecnologia de Setúbal, Setembro, 1998
[2] Motores passo-a-passo, António Abreu, Escola Superior de Tecnologia de
Setúbal, Setembro, 1998
[3] Dispositivos Electrónicos e Teoria de Circuitos, Sexta Edição, Robert L.
Boylrstad e Louis Nashelsky, LTC Editora, 1996
[4] http://209.41.165.153/stepper/Tutorials/UniTutor.htm
[5] http://www.cefetpr.br/deptos/daelt/eletronica/disp_optoelet.pdf
[6] http://www.imagingpg.com/products/products.asp?cat=30#88
[7] http://www.arquimedes.net/sens/sensor_de_luz_2.htm
[8] Electronic Devices And Circuits, First Edition, Michael Hassul e Don
Zimmerman, Prentice Hall, 1997
ANEXOS
ÍNDICE
ANEXO A – Datasheets ANEXO A.1 – AT89C51 ANEXO A.2 – MAX233A ANEXO A.3 – MX7828 ANEXO A.4 – SAA1042 ANEXO A.5 – 7805 ANEXO A.6 – BD243
ANEXO B – Esquemático ANEXO B.1 – Drivers ANEXO B.2 – Principal ANEXO C – PCB ANEXO C.1 – Drivers ANEXO C.2 – Principal ANEXO C.3 – Pistas para os contactos deslizantes ANEXO D – Programa do Microcontrolador ANEXO D.1 – Sem Ligação ao PC ANEXO D.2 – Com ligação ao PC ANEXO E – Programa em Visual Basic ANEXO F – Lista de material
ANEXO G – Desenho em Mechanical
ANEXO A – Datasheets
ANEXO A.1 – AT89C51
8-bit Microcontroller with 4K Bytes Flash
AT89C51
Not Recommended
Features• Compatible with MCS-51™ Products• 4K Bytes of In-System Reprogrammable Flash Memory
– Endurance: 1,000 Write/Erase Cycles• Fully Static Operation: 0 Hz to 24 MHz• Three-level Program Memory Lock• 128 x 8-bit Internal RAM• 32 Programmable I/O Lines• Two 16-bit Timer/Counters• Six Interrupt Sources• Programmable Serial Channel• Low-power Idle and Power-down Modes
DescriptionThe AT89C51 is a low-power, high-performance CMOS 8-bit microcomputer with 4Kbytes of Flash programmable and erasable read only memory (PEROM). The deviceis manufactured using Atmel’s high-density nonvolatile memory technology and iscompatible with the industry-standard MCS-51 instruction set and pinout. The on-chipFlash allows the program memory to be reprogrammed in-system or by a conven-tional nonvolatile memory programmer. By combining a versatile 8-bit CPU with Flashon a monolithic chip, the Atmel AT89C51 is a powerful microcomputer which providesa highly-flexible and cost-effective solution to many embedded control applications.
1
PQFP/TQFP
1234567891011
3332313029282726252423
P1.5P1.6P1.7RST
(RXD) P3.0NC
(TXD) P3.1(INT0) P3.2(INT1) P3.3
(T0) P3.4(T1) P3.5
PO.4 (AD4)P0.5 (AD5)P0.6 (AD6)P0.7 (AD7)EA/VPPNCALE/PROGPSENP2.7 (A15)P2.6 (A14)P2.5 (A13)
44 43 42 41 40 39 38 37 36 35 34
12 13 14 15 16 17 18 19 20 21 22
(WR
)P3.
6(R
D)
P3.
7X
TA
L2X
TA
L1G
ND
GN
D(A
8) P
2.0
(A9)
P2.
1(A
10)
P2.
2(A
11)
P2.
3(A
12)
P2.
4
P1.
4P
1.3
P1.
2 P
1.1
(T2
EX
)P
1.0
(T2)
NC
VC
CP
0.0
(AD
0)P
0.1
(AD
1)P
0.2
(AD
2)P
0.3
(AD
3)
PDIP
1234567891011121314151617181920
4039383736353433323130292827262524232221
P1.0 P1.1P1.2P1.3P1.4P1.5P1.6P1.7RST
(RXD) P3.0(TXD) P3.1(INT0) P3.2(INT1) P3.3
(T0) P3.4(T1) P3.5
(WR) P3.6(RD) P3.7
XTAL2XTAL1
GND
VCCP0.0 (AD0)P0.1 (AD1)P0.2 (AD2)P0.3 (AD3)P0.4 (AD4)P0.5 (AD5)P0.6 (AD6)P0.7 (AD7)EA/VPPALE/PROGPSENP2.7 (A15)P2.6 (A14)P2.5 (A13)P2.4 (A12)P2.3 (A11)P2.2 (A10)P2.1 (A9)P2.0 (A8)
Rev. 0265G–02/00
for New Designs. Use AT89S51.
Pin Configurations
PLCC
7891011121314151617
3938373635343332313029
P1.5P1.6P1.7RST
(RXD) P3.0NC
(TXD) P3.1(INT0) P3.2(INT1) P3.3
(T0) P3.4(T1) P3.5
PO.4 (AD4)P0.5 (AD5)P0.6 (AD6)P0.7 (AD7)EA/VPPNCALE/PROGPSENP2.7 (A15)P2.6 (A14)P2.5 (A13)
6 5 4 3 2 1 44 43 42 41 40
18 19 20 21 22 23 24 25 26 27 28
(WR
)P3.
6(R
D)
P3.
7X
TA
L2X
TA
L1G
ND
NC
(A8)
P2.
0(A
9) P
2.1
(A10
) P
2.2
(A11
) P
2.3
(A12
) P
2.4
P1.
4P
1.3
P1.
2 P
1.1
P1.
0N
CV
CC
P0.
0 (A
D0)
P0.
1 (A
D1)
P0.
2 (A
D2)
P0.
3 (A
D3)
AT89C512
Block Diagram
PORT 2 DRIVERS
PORT 2LATCH
P2.0 - P2.7
FLASHPORT 0LATCHRAM
PROGRAMADDRESSREGISTER
BUFFER
PCINCREMENTER
PROGRAMCOUNTER
DPTR
RAM ADDR.REGISTER
INSTRUCTIONREGISTER
BREGISTER
INTERRUPT, SERIAL PORT,AND TIMER BLOCKS
STACKPOINTERACC
TMP2 TMP1
ALU
PSW
TIMINGAND
CONTROL
PORT 3LATCH
PORT 3 DRIVERS
P3.0 - P3.7
PORT 1LATCH
PORT 1 DRIVERS
P1.0 - P1.7
OSC
GND
VCC
PSEN
ALE/PROG
EA / VPP
RST
PORT 0 DRIVERS
P0.0 - P0.7
AT89C51
The AT89C51 provides the following standard features: 4Kbytes of Flash, 128 bytes of RAM, 32 I/O lines, two 16-bittimer/counters, a five vector two-level interrupt architecture,a full duplex serial port, on-chip oscillator and clock cir-cuitry. In addition, the AT89C51 is designed with static logicfor operation down to zero frequency and supports twosoftware selectable power saving modes. The Idle Modestops the CPU while allowing the RAM, timer/counters,serial port and interrupt system to continue functioning. ThePower-down Mode saves the RAM contents but freezesthe oscillator disabling all other chip functions until the nexthardware reset.
Pin Description
VCC
Supply voltage.
GND
Ground.
Port 0
Port 0 is an 8-bit open-drain bi-directional I/O port. As anoutput port, each pin can sink eight TTL inputs. When 1sare written to port 0 pins, the pins can be used as high-impedance inputs.
Port 0 may also be configured to be the multiplexed low-order address/data bus during accesses to external pro-gram and data memory. In this mode P0 has internalpullups.
Port 0 also receives the code bytes during Flash program-ming, and outputs the code bytes during programverification. External pullups are required during programverification.
Port 1
Port 1 is an 8-bit bi-directional I/O port with internal pullups.The Port 1 output buffers can sink/source four TTL inputs.When 1s are written to Port 1 pins they are pulled high bythe internal pullups and can be used as inputs. As inputs,Port 1 pins that are externally being pulled low will sourcecurrent (IIL) because of the internal pullups.
Port 1 also receives the low-order address bytes duringFlash programming and verification.
Port 2
Port 2 is an 8-bit bi-directional I/O port with internal pullups.The Port 2 output buffers can sink/source four TTL inputs.When 1s are written to Port 2 pins they are pulled high bythe internal pullups and can be used as inputs. As inputs,
Port 2 pins that are externally being pulled low will sourcecurrent (IIL) because of the internal pullups.
Port 2 emits the high-order address byte during fetchesfrom external program memory and during accesses toexternal data memory that use 16-bit addresses (MOVX @DPTR). In this application, it uses strong internal pullupswhen emitting 1s. During accesses to external data mem-ory that use 8-bit addresses (MOVX @ RI), Port 2 emits thecontents of the P2 Special Function Register.
Port 2 also receives the high-order address bits and somecontrol signals during Flash programming and verification.
Port 3
Port 3 is an 8-bit bi-directional I/O port with internal pullups.The Port 3 output buffers can sink/source four TTL inputs.When 1s are written to Port 3 pins they are pulled high bythe internal pullups and can be used as inputs. As inputs,Port 3 pins that are externally being pulled low will sourcecurrent (IIL) because of the pullups.
Port 3 also serves the functions of various special featuresof the AT89C51 as listed below:
Port 3 also receives some control signals for Flash pro-gramming and verification.
RST
Reset input. A high on this pin for two machine cycles whilethe oscillator is running resets the device.
ALE/PROG
Address Latch Enable output pulse for latching the low byteof the address during accesses to external memory. Thispin is also the program pulse input (PROG) during Flashprogramming.
In normal operation ALE is emitted at a constant rate of 1/6the oscillator frequency, and may be used for external tim-ing or clocking purposes. Note, however, that one ALE
Port Pin Alternate Functions
P3.0 RXD (serial input port)
P3.1 TXD (serial output port)
P3.2 INT0 (external interrupt 0)
P3.3 INT1 (external interrupt 1)
P3.4 T0 (timer 0 external input)
P3.5 T1 (timer 1 external input)
P3.6 WR (external data memory write strobe)
P3.7 RD (external data memory read strobe)
3
pulse is skipped during each access to external DataMemory.
If desired, ALE operation can be disabled by setting bit 0 ofSFR location 8EH. With the bit set, ALE is active only dur-ing a MOVX or MOVC instruction. Otherwise, the pin isweakly pulled high. Setting the ALE-disable bit has noeffect if the microcontroller is in external execution mode.
PSEN
Program Store Enable is the read strobe to external pro-gram memory.
When the AT89C51 is executing code from external pro-gram memory, PSEN is activated twice each machinecycle, except that two PSEN activations are skipped duringeach access to external data memory.
EA/VPP
External Access Enable. EA must be strapped to GND inorder to enable the device to fetch code from external pro-gram memory locations starting at 0000H up to FFFFH.Note, however, that if lock bit 1 is programmed, EA will beinternally latched on reset.
EA should be strapped to VCC for internal programexecutions.
This pin also receives the 12-volt programming enable volt-age (VPP) during Flash programming, for parts that require12-volt VPP.
XTAL1
Input to the inverting oscillator amplifier and input to theinternal clock operating circuit.
XTAL2
Output from the inverting oscillator amplifier.
Oscillator Characteristics XTAL1 and XTAL2 are the input and output, respectively,of an inverting amplifier which can be configured for use asan on-chip oscillator, as shown in Figure 1. Either a quartzcrystal or ceramic resonator may be used. To drive thedevice from an external clock source, XTAL2 should be left
unconnected while XTAL1 is driven as shown in Figure 2.There are no requirements on the duty cycle of the externalclock signal, since the input to the internal clocking circuitryis through a divide-by-two flip-flop, but minimum and maxi-mum voltage high and low time specifications must beobserved.
Idle Mode In idle mode, the CPU puts itself to sleep while all the on-chip peripherals remain active. The mode is invoked bysoftware. The content of the on-chip RAM and all the spe-cial functions registers remain unchanged during thismode. The idle mode can be terminated by any enabledinterrupt or by a hardware reset.
It should be noted that when idle is terminated by a hardware reset, the device normally resumes program execu-tion, from where it left off, up to two machine cycles beforethe internal reset algorithm takes control. On-chip hardwareinhibits access to internal RAM in this event, but access tothe port pins is not inhibited. To eliminate the possibility ofan unexpected write to a port pin when Idle is terminated byreset, the instruction following the one that invokes Idleshould not be one that writes to a port pin or to externalmemory.
Figure 1. Oscillator Connections
Note: C1, C2 = 30 pF ± 10 pF for Crystals= 40 pF ± 10 pF for Ceramic Resonators
C2XTAL2
GND
XTAL1C1
Status of External Pins During Idle and Power-down ModesMode Program Memory ALE PSEN PORT0 PORT1 PORT2 PORT3
Idle Internal 1 1 Data Data Data Data
Idle External 1 1 Float Data Address Data
Power-down Internal 0 0 Data Data Data Data
Power-down External 0 0 Float Data Data Data
AT89C514
AT89C51
Figure 2. External Clock Drive Configuration
Power-down Mode In the power-down mode, the oscillator is stopped, and theinstruction that invokes power-down is the last instructionexecuted. The on-chip RAM and Special Function Regis-
ters retain their values until the power-down mode isterminated. The only exit from power-down is a hardwarereset. Reset redefines the SFRs but does not change theon-chip RAM. The reset should not be activated before VCCis restored to its normal operating level and must be heldactive long enough to allow the oscillator to restart andstabilize.
Program Memory Lock Bits On the chip are three lock bits which can be left unpro-grammed (U) or can be programmed (P) to obtain theadditional features listed in the table below.
When lock bit 1 is programmed, the logic level at the EA pinis sampled and latched during reset. If the device is pow-ered up without a reset, the latch initializes to a randomvalue, and holds that value until reset is activated. It is nec-essary that the latched value of EA be in agreement withthe current logic level at that pin in order for the device tofunction properly.
Lock Bit Protection ModesProgram Lock Bits
Protection TypeLB1 LB2 LB3
1 U U U No program lock features
2 P U U MOVC instructions executed from external program memory are disabled from fetching code bytes from internal memory, EA is sampled and latched on reset, and further programming of the Flash is disabled
3 P P U Same as mode 2, also verify is disabled
4 P P P Same as mode 3, also external execution is disabled
5
Programming the Flash The AT89C51 is normally shipped with the on-chip Flashmemory array in the erased state (that is, contents = FFH)and ready to be programmed. The programming interfaceaccepts either a high-voltage (12-volt) or a low-voltage(VCC) program enable signal. The low-voltage program-ming mode provides a convenient way to program theAT89C51 inside the user’s system, while the high-voltageprogramming mode is compatible with conventional third-party Flash or EPROM programmers.
The AT89C51 is shipped with either the high-voltage orlow-voltage programming mode enabled. The respectivetop-side marking and device signature codes are listed inthe following table.
The AT89C51 code memory array is programmed byte-by-byte in either programming mode. To program any non-blank byte in the on-chip Flash Memory, the entire memorymust be erased using the Chip Erase Mode.
Programming Algorithm: Before programming theAT89C51, the address, data and control signals should beset up according to the Flash programming mode table andFigure 3 and Figure 4. To program the AT89C51, take thefollowing steps.
1. Input the desired memory location on the address lines.
2. Input the appropriate data byte on the data lines.
3. Activate the correct combination of control signals.
4. Raise EA/VPP to 12V for the high-voltage program-ming mode.
5. Pulse ALE/PROG once to program a byte in the Flash array or the lock bits. The byte-write cycle is self-timed and typically takes no more than 1.5 ms. Repeat steps 1 through 5, changing the address
and data for the entire array or until the end of the object file is reached.
Data Polling: The AT89C51 features Data Polling to indi-cate the end of a write cycle. During a write cycle, anattempted read of the last byte written will result in the com-plement of the written datum on PO.7. Once the write cyclehas been completed, true data are valid on all outputs, andthe next cycle may begin. Data Polling may begin any timeafter a write cycle has been initiated.
Ready/Busy: The progress of byte programming can alsobe monitored by the RDY/BSY output signal. P3.4 is pulledlow after ALE goes high during programming to indicateBUSY. P3.4 is pulled high again when programming isdone to indicate READY.
Program Verify: If lock bits LB1 and LB2 have not beenprogrammed, the programmed code data can be read backvia the address and data lines for verification. The lock bitscannot be verified directly. Verification of the lock bits isachieved by observing that their features are enabled.
Chip Erase: The entire Flash array is erased electricallyby using the proper combination of control signals and byholding ALE/PROG low for 10 ms. The code array is writtenwith all “1”s. The chip erase operation must be executedbefore the code memory can be re-programmed.
Reading the Signature Bytes: The signature bytes areread by the same procedure as a normal verification oflocations 030H, 031H, and 032H, except that P3.6 andP3.7 must be pulled to a logic low. The values returned areas follows.
(030H) = 1EH indicates manufactured by Atmel(031H) = 51H indicates 89C51(032H) = FFH indicates 12V programming(032H) = 05H indicates 5V programming
Programming InterfaceEvery code byte in the Flash array can be written and theentire array can be erased by using the appropriate combi-nation of control signals. The write operation cycle is self-timed and once initiated, will automatically time itself tocompletion.
All major programming vendors offer worldwide support forthe Atmel microcontroller series. Please contact your localprogramming vendor for the appropriate software revision.
VPP = 12V VPP = 5V
Top-side Mark AT89C51xxxx
yyww
AT89C51xxxx-5
yyww
Signature (030H) = 1EH
(031H) = 51H(032H) =F FH
(030H) = 1EH
(031H) = 51H(032H) = 05H
AT89C516
AT89C51
Note: 1. Chip Erase requires a 10 ms PROG pulse.
Figure 3. Programming the Flash Figure 4. Verifying the Flash
Flash Programming ModesMode RST PSEN ALE/PROG EA/VPP P2.6 P2.7 P3.6 P3.7
Write Code Data H L H/12V L H H H
Read Code Data H L H H L L H H
Write Lock Bit - 1 H L H/12V H H H H
Bit - 2 H L H/12V H H L L
Bit - 3 H L H/12V H L H L
Chip Erase H L H/12V H L L L
Read Signature Byte H L H H L L L L
(1)
P1
P2.6
P3.6
P2.0 - P2.3
A0 - A7ADDR.
OOOOH/OFFFH
T
SEE FLASHPROGRAMMINGMODES ABLE
3-24 MHz
A8 - A11P0
+5V
P2.7
PGMDATA
PROG
V /VIH PP
VIH
ALE
P3.7
XTAL2 EA
RST
PSEN
XTAL1
GND
VCC
AT89C51
P1
P2.6
P3.6
P2.0 - P2.3
A0 - A7ADDR.
OOOOH/0FFFH
3-24 MHz
A8 - A11P0
+5V
P2.7
PGM DATA(USE 10KPULLUPS)
VIH
VIH
ALE
P3.7
XTAL2 EA
RST
PSEN
XTAL1
GND
VCC
AT89C51
T
SEE FLASHPROGRAMMINGMODES ABLE
7
Flash Programming and Verification Waveforms - High-voltage Mode (VPP = 12V)
Flash Programming and Verification Waveforms - Low-voltage Mode (VPP = 5V)
tGLGHtGHSL
tAVGL
tSHGL
tDVGLtGHAX
tAVQV
tGHDX
tEHSH tELQV
tWC
BUSY READY
tGHBL
tEHQZ
P1.0 - P1.7P2.0 - P2.3
ALE/PROG
PORT 0
LOGIC 1LOGIC 0EA/VPP
VPP
P2.7(ENABLE)
P3.4(RDY/BSY)
PROGRAMMINGADDRESS
VERIFICATIONADDRESS
DATA IN DATA OUT
tGLGH
tAVGL
tSHGL
tDVGLtGHAX
tAVQV
tGHDX
tEHSH tELQV
tWC
BUSY READY
tGHBL
tEHQZ
P1.0 - P1.7P2.0 - P2.3
ALE/PROG
PORT 0
LOGIC 1LOGIC 0EA/VPP
P2.7(ENABLE)
P3.4(RDY/BSY)
PROGRAMMINGADDRESS
VERIFICATIONADDRESS
DATA IN DATA OUT
AT89C518
AT89C51
Note: 1. Only used in 12-volt programming mode.
Flash Programming and Verification Characteristics TA = 0°C to 70°C, VCC = 5.0 ± 10%
Symbol Parameter Min Max Units
VPP(1) Programming Enable Voltage 11.5 12.5 V
IPP(1) Programming Enable Current 1.0 mA
1/tCLCL Oscillator Frequency 3 24 MHz
tAVGL Address Setup to PROG Low 48tCLCL
tGHAX Address Hold after PROG 48tCLCL
tDVGL Data Setup to PROG Low 48tCLCL
tGHDX Data Hold after PROG 48tCLCL
tEHSH P2.7 (ENABLE) High to VPP 48tCLCL
tSHGL VPP Setup to PROG Low 10 µs
tGHSL(1) VPP Hold after PROG 10 µs
tGLGH PROG Width 1 110 µs
tAVQV Address to Data Valid 48tCLCL
tELQV ENABLE Low to Data Valid 48tCLCL
tEHQZ Data Float after ENABLE 0 48tCLCL
tGHBL PROG High to BUSY Low 1.0 µs
tWC Byte Write Cycle Time 2.0 ms
9
Absolute Maximum Ratings*
Notes: 1. Under steady state (non-transient) conditions, IOL must be externally limited as follows:Maximum IOL per port pin: 10 mAMaximum IOL per 8-bit port: Port 0: 26 mAPorts 1, 2, 3: 15 mAMaximum total IOL for all output pins: 71 mAIf IOL exceeds the test condition, VOL may exceed the related specification. Pins are not guaranteed to sink current greater than the listed test conditions.
2. Minimum VCC for Power-down is 2V.
Operating Temperature.................................. -55°C to +125°C *NOTICE: Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent dam-age to the device. This is a stress rating only and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
Storage Temperature ..................................... -65°C to +150°C
Voltage on Any Pinwith Respect to Ground .....................................-1.0V to +7.0V
Maximum Operating Voltage ............................................ 6.6V
DC Output Current...................................................... 15.0 mA
DC CharacteristicsTA = -40°C to 85°C, VCC = 5.0V ± 20% (unless otherwise noted)
Symbol Parameter Condition Min Max Units
VIL Input Low-voltage (Except EA) -0.5 0.2 VCC - 0.1 V
VIL1 Input Low-voltage (EA) -0.5 0.2 VCC - 0.3 V
VIH Input High-voltage (Except XTAL1, RST) 0.2 VCC + 0.9 VCC + 0.5 V
VIH1 Input High-voltage (XTAL1, RST) 0.7 VCC VCC + 0.5 V
VOL Output Low-voltage(1) (Ports 1,2,3) IOL = 1.6 mA 0.45 V
VOL1Output Low-voltage(1)
(Port 0, ALE, PSEN)IOL = 3.2 mA 0.45 V
VOHOutput High-voltage(Ports 1,2,3, ALE, PSEN)
IOH = -60 µA, VCC = 5V ± 10% 2.4 V
IOH = -25 µA 0.75 VCC V
IOH = -10 µA 0.9 VCC V
VOH1Output High-voltage(Port 0 in External Bus Mode)
IOH = -800 µA, VCC = 5V ± 10% 2.4 V
IOH = -300 µA 0.75 VCC V
IOH = -80 µA 0.9 VCC V
IIL Logical 0 Input Current (Ports 1,2,3) VIN = 0.45V -50 µA
ITLLogical 1 to 0 Transition Current (Ports 1,2,3)
VIN = 2V, VCC = 5V ± 10% -650 µA
ILI Input Leakage Current (Port 0, EA) 0.45 < VIN < VCC ±10 µA
RRST Reset Pull-down Resistor 50 300 KΩ
CIO Pin Capacitance Test Freq. = 1 MHz, TA = 25°C 10 pF
ICC
Power Supply CurrentActive Mode, 12 MHz 20 mA
Idle Mode, 12 MHz 5 mA
Power-down Mode(2)VCC = 6V 100 µA
VCC = 3V 40 µA
AT89C5110
AT89C51
AC CharacteristicsUnder operating conditions, load capacitance for Port 0, ALE/PROG, and PSEN = 100 pF; load capacitance for all other outputs = 80 pF.
External Program and Data Memory Characteristics
Symbol Parameter
12 MHz Oscillator 16 to 24 MHz Oscillator
UnitsMin Max Min Max
1/tCLCL Oscillator Frequency 0 24 MHz
tLHLL ALE Pulse Width 127 2tCLCL-40 ns
tAVLL Address Valid to ALE Low 43 tCLCL-13 ns
tLLAX Address Hold after ALE Low 48 tCLCL-20 ns
tLLIV ALE Low to Valid Instruction In 233 4tCLCL-65 ns
tLLPL ALE Low to PSEN Low 43 tCLCL-13 ns
tPLPH PSEN Pulse Width 205 3tCLCL-20 ns
tPLIV PSEN Low to Valid Instruction In 145 3tCLCL-45 ns
tPXIX Input Instruction Hold after PSEN 0 0 ns
tPXIZ Input Instruction Float after PSEN 59 tCLCL-10 ns
tPXAV PSEN to Address Valid 75 tCLCL-8 ns
tAVIV Address to Valid Instruction In 312 5tCLCL-55 ns
tPLAZ PSEN Low to Address Float 10 10 ns
tRLRH RD Pulse Width 400 6tCLCL-100 ns
tWLWH WR Pulse Width 400 6tCLCL-100 ns
tRLDV RD Low to Valid Data In 252 5tCLCL-90 ns
tRHDX Data Hold after RD 0 0 ns
tRHDZ Data Float after RD 97 2tCLCL-28 ns
tLLDV ALE Low to Valid Data In 517 8tCLCL-150 ns
tAVDV Address to Valid Data In 585 9tCLCL-165 ns
tLLWL ALE Low to RD or WR Low 200 300 3tCLCL-50 3tCLCL+50 ns
tAVWL Address to RD or WR Low 203 4tCLCL-75 ns
tQVWX Data Valid to WR Transition 23 tCLCL-20 ns
tQVWH Data Valid to WR High 433 7tCLCL-120 ns
tWHQX Data Hold after WR 33 tCLCL-20 ns
tRLAZ RD Low to Address Float 0 0 ns
tWHLH RD or WR High to ALE High 43 123 tCLCL-20 tCLCL+25 ns
11
External Program Memory Read Cycle
External Data Memory Read Cycle
tLHLL
tLLIV
tPLIV
tLLAXtPXIZ
tPLPH
tPLAZtPXAV
tAVLL tLLPL
tAVIV
tPXIX
ALE
PSEN
PORT 0
PORT 2 A8 - A15
A0 - A7 A0 - A7
A8 - A15
INSTR IN
tLHLL
tLLDV
tLLWL
tLLAX
tWHLH
tAVLL
tRLRH
tAVDV
tAVWL
tRLAZ tRHDX
tRLDV tRHDZ
A0 - A7 FROM RI OR DPL
ALE
PSEN
RD
PORT 0
PORT 2 P2.0 - P2.7 OR A8 - A15 FROM DPH
A0 - A7 FROM PCL
A8 - A15 FROM PCH
DATA IN INSTR IN
AT89C5112
AT89C51
External Data Memory Write Cycle
External Clock Drive Waveforms
External Clock DriveSymbol Parameter Min Max Units
1/tCLCL Oscillator Frequency 0 24 MHz
tCLCL Clock Period 41.6 ns
tCHCX High Time 15 ns
tCLCX Low Time 15 ns
tCLCH Rise Time 20 ns
tCHCL Fall Time 20 ns
tLHLL
tLLWL
tLLAX
tWHLH
tAVLL
tWLWH
tAVWL
tQVWXtQVWH
tWHQX
A0 - A7 FROM RI OR DPL
ALE
PSEN
WR
PORT 0
PORT 2 P2.0 - P2.7 OR A8 - A15 FROM DPH
A0 - A7 FROM PCL
A8 - A15 FROM PCH
DATA OUT INSTR IN
tCHCX
tCHCX
tCLCX
tCLCL
tCHCLtCLCHV - 0.5VCC
0.45V0.2 V - 0.1VCC
0.7 VCC
13
Shift Register Mode Timing Waveforms
AC Testing Input/Output Waveforms(1)
Note: 1. AC Inputs during testing are driven at VCC - 0.5V for a logic 1 and 0.45V for a logic 0. Timing measurements are made at VIH min. for a logic 1 and VIL max. for a logic 0.
Float Waveforms(1)
Note: 1. For timing purposes, a port pin is no longer floating when a 100 mV change from load voltage occurs. A port pin begins to float when 100 mV change from the loaded VOH/VOL level occurs.
Serial Port Timing: Shift Register Mode Test Conditions(VCC = 5.0 V ± 20%; Load Capacitance = 80 pF)
Symbol Parameter
12 MHz Osc Variable Oscillator Units
Min Max Min Max
tXLXL Serial Port Clock Cycle Time 1.0 12tCLCL µs
tQVXH Output Data Setup to Clock Rising Edge 700 10tCLCL-133 ns
tXHQX Output Data Hold after Clock Rising Edge 50 2tCLCL-117 ns
tXHDX Input Data Hold after Clock Rising Edge 0 0 ns
tXHDV Clock Rising Edge to Input Data Valid 700 10tCLCL-133 ns
tXHDV
tQVXH
tXLXL
tXHDX
tXHQX
ALE
INPUT DATA
CLEAR RI
OUTPUT DATA
WRITE TO SBUF
INSTRUCTION
CLOCK
0
0
1
1
2
2
3
3
4
4
5
5
6
6
7
7
SET TI
SET RI
8
VALID VALIDVALID VALIDVALID VALIDVALID VALID
0.45V
TEST POINTS
V - 0.5VCC 0.2 V + 0.9VCC
0.2 V - 0.1VCC
VLOAD+ 0.1V
Timing ReferencePoints
V
LOAD- 0.1V
LOAD
V VOL+ 0.1V
VOL- 0.1V
AT89C5114
AT89C51
Ordering InformationSpeed(MHz)
PowerSupply Ordering Code Package Operation Range
12 5V ± 20% AT89C51-12AC 44A Commercial
AT89C51-12JC 44J (0° C to 70° C)
AT89C51-12PC 40P6
AT89C51-12QC 44Q
AT89C51-12AI 44A Industrial
AT89C51-12JI 44J (-40° C to 85° C)
AT89C51-12PI 40P6
AT89C51-12QI 44Q
16 5V ± 20% AT89C51-16AC 44A Commercial
AT89C51-16JC 44J (0° C to 70° C)
AT89C51-16PC 40P6
AT89C51-16QC 44Q
AT89C51-16AI 44A Industrial
AT89C51-16JI 44J (-40° C to 85° C)
AT89C51-16PI 40P6
AT89C51-16QI 44Q
20 5V ± 20% AT89C51-20AC 44A Commercial
AT89C51-20JC 44J (0° C to 70° C)
AT89C51-20PC 40P6
AT89C51-20QC 44Q
AT89C51-20AI 44A Industrial
AT89C51-20JI 44J (-40° C to 85° C)
AT89C51-20PI 40P6
AT89C51-20QI 44Q
24 5V ± 20% AT89C51-24AC 44A Commercial
AT89C51-24JC 44J (0° C to 70° C)
AT89C51-24PC 40P6
AT89C51-24QC 44Q
AT89C51-24AI 44A Industrial
AT89C51-24JI 44J (-40° C to 85° C)
AT89C51-24PI 40P6
AT89C51-24QI 44Q
15
Package Type
44A 44-lead, Thin Plastic Gull Wing Quad Flatpack (TQFP)
44J 44-lead, Plastic J-leaded Chip Carrier (PLCC)
40P6 40-lead, 0.600” Wide, Plastic Dual Inline Package (PDIP)
44Q 44-lead, Plastic Gull Wing Quad Flatpack (PQFP)
Packaging Information
Controlling dimension: millimeters
1.20(0.047) MAX
10.10(0.394)9.90(0.386)
SQ
12.21(0.478)11.75(0.458)
SQ
0.75(0.030)0.45(0.018)
0.15(0.006)0.05(0.002)
0.20(.008)0.09(.003)
07
0.80(0.031) BSC
PIN 1 ID
0.45(0.018)0.30(0.012)
JEDEC STANDARD MS-026 ACB
AT89C5116
.045(1.14) X 45° PIN NO. 1IDENTIFY
.045(1.14) X 30° - 45° .012(.305).008(.203)
.021(.533)
.013(.330)
.630(16.0)
.590(15.0)
.043(1.09)
.020(.508)
.120(3.05)
.090(2.29).180(4.57).165(4.19)
.500(12.7) REF SQ
.032(.813)
.026(.660)
.050(1.27) TYP
.022(.559) X 45° MAX (3X)
.656(16.7)
.650(16.5)
.695(17.7)
.685(17.4)SQ
SQ
2.07(52.6)2.04(51.8) PIN
1
.566(14.4)
.530(13.5)
.090(2.29)MAX
.005(.127)MIN
.065(1.65)
.015(.381)
.022(.559)
.014(.356).065(1.65).041(1.04)
015
REF
.690(17.5)
.610(15.5)
.630(16.0)
.590(15.0)
.012(.305)
.008(.203)
.110(2.79)
.090(2.29)
.161(4.09)
.125(3.18)
SEATINGPLANE
.220(5.59)MAX
1.900(48.26) REF
Controlling dimension: millimeters
13.45 (0.525)12.95 (0.506)
0.50 (0.020)0.35 (0.014)
SQ
PIN 1 ID
0.80 (0.031) BSC
10.10 (0.394)9.90 (0.386) SQ
070.17 (0.007)
0.13 (0.005)
1.03 (0.041)0.78 (0.030)
2.45 (0.096) MAX
0.25 (0.010) MAX
44A, 44-lead, Thin (1.0 mm) Plastic Gull Wing Quad Flatpack (TQFP)Dimensions in Millimeters and (Inches)*
44J, 44-lead, Plastic J-leaded Chip Carrier (PLCC)Dimensions in Inches and (Millimeters)JEDEC STANDARD MS-018 AC
40P6, 40-lead, 0.600" Wide, Plastic Dual Inline Package (PDIP)Dimensions in Inches and (Millimeters)
44Q, 44-lead, Plastic Quad Flat Package (PQFP)Dimensions in Millimeters and (Inches)*JEDEC STANDARD MS-022 AB
© Atmel Corporation 2000.Atmel Corporation makes no warranty for the use of its products, other than those expressly contained in the Company’s standard war-ranty which is detailed in Atmel’s Terms and Conditions located on the Company’s web site. The Company assumes no responsibility forany errors which may appear in this document, reserves the right to change devices or specifications detailed herein at any time withoutnotice, and does not make any commitment to update the information contained herein. No licenses to patents or other intellectual prop-erty of Atmel are granted by the Company in connection with the sale of Atmel products, expressly or by implication. Atmel’s products arenot authorized for use as critical components in life support devices or systems.
Atmel Headquarters Atmel Operations
Corporate Headquarters2325 Orchard ParkwaySan Jose, CA 95131TEL (408) 441-0311FAX (408) 487-2600
EuropeAtmel U.K., Ltd.Coliseum Business CentreRiverside WayCamberley, Surrey GU15 3YLEnglandTEL (44) 1276-686-677FAX (44) 1276-686-697
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Fax-on-DemandNorth America:1-(800) 292-8635
International:1-(408) 441-0732
e-mailliterature@atmel.com
Web Sitehttp://www.atmel.com
BBS1-(408) 436-4309
Printed on recycled paper.
0265G–02/00/xM
Marks bearing ® and/or ™ are registered trademarks and trademarks of Atmel Corporation.
Terms and product names in this document may be trademarks of others.
ANEXO A.2 – MAX233A
General DescriptionThe MAX220–MAX249 family of line drivers/receivers isintended for all EIA/TIA-232E and V.28/V.24 communica-tions interfaces, particularly applications where ±12V isnot available. These parts are especially useful in battery-powered sys-tems, since their low-power shutdown mode reducespower dissipation to less than 5µW. The MAX225,MAX233, MAX235, and MAX245/MAX246/MAX247 useno external components and are recommended for appli-cations where printed circuit board space is critical.
________________________ApplicationsPortable Computers
Low-Power Modems
Interface Translation
Battery-Powered RS-232 Systems
Multidrop RS-232 Networks
____________________________FeaturesSuperior to Bipolar Operate from Single +5V Power Supply
(+5V and +12V—MAX231/MAX239) Low-Power Receive Mode in Shutdown
(MAX223/MAX242) Meet All EIA/TIA-232E and V.28 Specifications Multiple Drivers and Receivers 3-State Driver and Receiver Outputs Open-Line Detection (MAX243)
Ordering Information
Ordering Information continued at end of data sheet.*Contact factory for dice specifications.
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________________________________________________________________ Maxim Integrated Products 1
Selection Table
19-4323; Rev 11; 2/03
PARTMAX220CPEMAX220CSEMAX220CWE 0°C to +70°C
0°C to +70°C0°C to +70°C
TEMP RANGE PIN-PACKAGE16 Plastic DIP16 Narrow SO16 Wide SO
MAX220C/D 0°C to +70°C Dice*MAX220EPEMAX220ESEMAX220EWE -40°C to +85°C
-40°C to +85°C-40°C to +85°C 16 Plastic DIP
16 Narrow SO16 Wide SO
MAX220EJE -40°C to +85°C 16 CERDIPMAX220MJE -55°C to +125°C 16 CERDIP
Power No. of Nominal SHDN RxPart Supply RS-232 No. of Cap. Value & Three- Active in Data RateNumber (V) Drivers/Rx Ext. Caps (µF) State SHDN (kbps) FeaturesMAX220 +5 2/2 4 0.1 No — 120 Ultra-low-power, industry-standard pinoutMAX222 +5 2/2 4 0.1 Yes — 200 Low-power shutdownMAX223 (MAX213) +5 4/5 4 1.0 (0.1) Yes 120 MAX241 and receivers active in shutdownMAX225 +5 5/5 0 — Yes 120 Available in SOMAX230 (MAX200) +5 5/0 4 1.0 (0.1) Yes — 120 5 drivers with shutdownMAX231 (MAX201) +5 and 2/2 2 1.0 (0.1) No — 120 Standard +5/+12V or battery supplies;
+7.5 to +13.2 same functions as MAX232MAX232 (MAX202) +5 2/2 4 1.0 (0.1) No — 120 (64) Industry standardMAX232A +5 2/2 4 0.1 No — 200 Higher slew rate, small capsMAX233 (MAX203) +5 2/2 0 — No — 120 No external capsMAX233A +5 2/2 0 — No — 200 No external caps, high slew rateMAX234 (MAX204) +5 4/0 4 1.0 (0.1) No — 120 Replaces 1488MAX235 (MAX205) +5 5/5 0 — Yes — 120 No external capsMAX236 (MAX206) +5 4/3 4 1.0 (0.1) Yes — 120 Shutdown, three stateMAX237 (MAX207) +5 5/3 4 1.0 (0.1) No — 120 Complements IBM PC serial portMAX238 (MAX208) +5 4/4 4 1.0 (0.1) No — 120 Replaces 1488 and 1489MAX239 (MAX209) +5 and 3/5 2 1.0 (0.1) No — 120 Standard +5/+12V or battery supplies;
+7.5 to +13.2 single-package solution for IBM PC serial portMAX240 +5 5/5 4 1.0 Yes — 120 DIP or flatpack packageMAX241 (MAX211) +5 4/5 4 1.0 (0.1) Yes — 120 Complete IBM PC serial portMAX242 +5 2/2 4 0.1 Yes 200 Separate shutdown and enableMAX243 +5 2/2 4 0.1 No — 200 Open-line detection simplifies cablingMAX244 +5 8/10 4 1.0 No — 120 High slew rateMAX245 +5 8/10 0 — Yes 120 High slew rate, int. caps, two shutdown modesMAX246 +5 8/10 0 — Yes 120 High slew rate, int. caps, three shutdown modesMAX247 +5 8/9 0 — Yes 120 High slew rate, int. caps, nine operating modesMAX248 +5 8/8 4 1.0 Yes 120 High slew rate, selective half-chip enablesMAX249 +5 6/10 4 1.0 Yes 120 Available in quad flatpack package
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
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2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS—MAX220/222/232A/233A/242/243
ELECTRICAL CHARACTERISTICS—MAX220/222/232A/233A/242/243(VCC = +5V ±10%, C1–C4 = 0.1µF‚ MAX220, C1 = 0.047µF, C2–C4 = 0.33µF, TA = TMIN to TMAX‚ unless otherwise noted.)
Note 1: Input voltage measured with TOUT in high-impedance state, SHDN or VCC = 0V.Note 2: For the MAX220, V+ and V- can have a maximum magnitude of 7V, but their absolute difference cannot exceed 13V.Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functionaloperation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure toabsolute maximum rating conditions for extended periods may affect device reliability.
Supply Voltage (VCC) ...............................................-0.3V to +6VInput VoltagesTIN..............................................................-0.3V to (VCC - 0.3V)RIN (Except MAX220) ........................................................±30VRIN (MAX220).....................................................................±25VTOUT (Except MAX220) (Note 1) .......................................±15VTOUT (MAX220)...............................................................±13.2V
Output VoltagesTOUT...................................................................................±15VROUT.........................................................-0.3V to (VCC + 0.3V)
Driver/Receiver Output Short Circuited to GND.........ContinuousContinuous Power Dissipation (TA = +70°C)16-Pin Plastic DIP (derate 10.53mW/°C above +70°C)....842mW18-Pin Plastic DIP (derate 11.11mW/°C above +70°C)....889mW
20-Pin Plastic DIP (derate 8.00mW/°C above +70°C) ..440mW16-Pin Narrow SO (derate 8.70mW/°C above +70°C) ...696mW16-Pin Wide SO (derate 9.52mW/°C above +70°C)......762mW18-Pin Wide SO (derate 9.52mW/°C above +70°C)......762mW20-Pin Wide SO (derate 10.00mW/°C above +70°C)....800mW20-Pin SSOP (derate 8.00mW/°C above +70°C) ..........640mW16-Pin CERDIP (derate 10.00mW/°C above +70°C).....800mW18-Pin CERDIP (derate 10.53mW/°C above +70°C).....842mW
Operating Temperature RangesMAX2_ _AC_ _, MAX2_ _C_ _.............................0°C to +70°CMAX2_ _AE_ _, MAX2_ _E_ _ ..........................-40°C to +85°CMAX2_ _AM_ _, MAX2_ _M_ _.......................-55°C to +125°C
Storage Temperature Range .............................-65°C to +160°CLead Temperature (soldering, 10s) .................................+300°C
V1.4 0.8Input Logic Threshold Low
UNITSMIN TYP MAXPARAMETER CONDITIONS
Input Logic Threshold HighAll devices except MAX220 2 1.4
V
All except MAX220, normal operation 5 40Logic Pull-Up/lnput Current
SHDN = 0V, MAX222/242, shutdown, MAX220 ±0.01 ±1µA
VCC = 5.5V, SHDN = 0V, VOUT = ±15V, MAX222/242 ±0.01 ±10Output Leakage Current
VCC = SHDN = 0V, VOUT = ±15V ±0.01 ±10µA
200 116Data Rate kbps
Transmitter Output Resistance VCC = V+ = V- = 0V, VOUT = ±2V 300 10M ΩOutput Short-Circuit Current VOUT = 0V ±7 ±22 mA
RS-232 Input Voltage Operating Range ±30 V
All except MAX243 R2IN 0.8 1.3RS-232 Input Threshold Low VCC = 5V
MAX243 R2IN (Note 2) -3V
All except MAX243 R2IN 1.8 2.4RS-232 Input Threshold High VCC = 5V
MAX243 R2IN (Note 2) -0.5 -0.1V
All except MAX243, VCC = 5V, no hysteresis in shdn. 0.2 0.5 1RS-232 Input Hysteresis
MAX243 1V
RS-232 Input Resistance 3 5 7 kΩTTL/CMOS Output Voltage Low IOUT = 3.2mA 0.2 0.4 V
TTL/CMOS Output Voltage High IOUT = -1.0mA 3.5 VCC - 0.2 V
Sourcing VOUT = GND -2 -10mATTL/CMOS Output Short-Circuit Current
Shrinking VOUT = VCC 10 30
V±5 ±8Output Voltage Swing All transmitter outputs loaded with 3kΩ to GND
RS-232 TRANSMITTERS
RS-232 RECEIVERS
2.4MAX220: VCC = 5.0V
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_______________________________________________________________________________________ 3
Note 3: MAX243 R2OUT is guaranteed to be low when R2IN is ≥ 0V or is floating.
ELECTRICAL CHARACTERISTICS—MAX220/222/232A/233A/242/243 (continued)(VCC = +5V ±10%, C1–C4 = 0.1µF‚ MAX220, C1 = 0.047µF, C2–C4 = 0.33µF, TA = TMIN to TMAX‚ unless otherwise noted.)
Operating Supply Voltage
SHDN Threshold High
4.5 5.5 V
MAX222/242
Transmitter-Output Enable Time (SHDN Goes High), Figure 4
2.0 1.4 V
MAX220 0.5 2
tET
No loadMAX222/232A/233A/242/243 4 10
MAX222/232A/233A/242/243 6 12 30
MAX220 12VCC Supply Current (SHDN = VCC),Figures 5, 6, 11, 19 3kΩ load
both inputs MAX222/232A/233A/242/243 15
mA
Transition Slew Rate
TA = +25°C 0.1 10
CL = 50pF to 2500pF, RL = 3kΩ to 7kΩ, VCC = 5V, TA = +25°C,measured from +3V to -3V or -3V to +3V
TA = 0°C to +70°C
CONDITIONS
2 50
MAX220 1.5 3 30
V/µs
TA = -40°C to +85°C 2 50
MAX222/242, 0.1µF caps(includes charge-pump start-up)
Shutdown Supply Current MAX222/242
TA = -55°C to +125°C 35 100
µA
SHDN Input Leakage Current MAX222/242 ±1 µA
SHDN Threshold Low MAX222/242 1.4 0.8 V
250
MAX222/232A/233A/242/243 1.3 3.5
µs
tPHLTMAX220 4 10
Transmitter-Output Disable Time (SHDN Goes Low), Figure 4
tDT
MAX222/232A/233A/242/243 1.5 3.5
Transmitter Propagation DelayTLL to RS-232 (Normal Operation), Figure 1 tPLHT
MAX220 5 10
µs
V2.0 1.4
MAX222/242, 0.1µF caps
µA±0.05 ±10
600
TTL/CMOS Output Leakage Current
EN Input Threshold High
MAX222/232A/233A/242/243 0.5 1
ns
tPHLRMAX220 0.6 3
tPLHRMAX222/232A/233A/242/243 0.6 1
Receiver Propagation DelayRS-232 to TLL (Normal Operation),Figure 2
tPHLT - tPLHT
MAX220 0.8 3
µs
MAX222/232A/233A/242/243
tPHLS MAX242 0.5 10Receiver Propagation Delay RS-232 to TLL (Shutdown), Figure 2 tPLHS MAX242 2.5 10
µs
Receiver-Output Enable Time, Figure 3 tER MAX242
UNITSMIN TYP MAX
125 500
PARAMETER
MAX242
ns
SHDN = VCC or EN = VCC (SHDN = 0V for MAX222),0V ≤ VOUT ≤ VCC
Receiver-Output Disable Time, Figure 3 tDR MAX242 160 500 ns
300ns
Transmitter + to - Propagation Delay Difference (Normal Operation) MAX220 2000
tPHLR - tPLHRMAX222/232A/233A/242/243 100
nsReceiver + to - Propagation Delay Difference (Normal Operation) MAX220 225
V1.4 0.8EN Input Threshold Low MAX242
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
4 _______________________________________________________________________________________
__________________________________________Typical Operating Characteristics
MAX220/MAX222/MAX232A/MAX233A/MAX242/MAX243
10
8
-100 5 15 25
OUTPUT VOLTAGE vs. LOAD CURRENT
-4
-6
-8
-2
6
4
2
MAX
220-
01
LOAD CURRENT (mA)
OUTP
UT V
OLTA
GE (V
)
10
0
20
0.1µF
EITHER V+ OR V- LOADED
VCC = ±5VNO LOAD ONTRANSMITTER OUTPUTS(EXCEPT MAX220, MAX233A)
V- LOADED, NO LOAD ON V+
V+ LOADED, NO LOAD ON V-
1µF
1µF0.1µF
11
10
40 10 40 60
AVAILABLE OUTPUT CURRENTvs. DATA RATE
6
5
7
9
8
MAX
220-
02
DATA RATE (kbits/sec)
OUTP
UT C
URRE
NT (m
A)
20 30 50
OUTPUT LOAD CURRENTFLOWS FROM V+ TO V-
VCC = +5.25V
ALL CAPS1µF
ALL CAPS0.1µF
VCC = +4.75V
+10V
-10V
MAX222/MAX242ON-TIME EXITING SHUTDOWN
+5V+5V
0V
0V
MAX
220-
03
500µs/div
V+, V
- VOL
TAGE
(V)
1µF CAPSV+
V+
V-V-
SHDN
0.1µF CAPS
1µF CAPS
0.1µF CAPS
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
_______________________________________________________________________________________ 5
VCC...........................................................................-0.3V to +6VV+................................................................(VCC - 0.3V) to +14VV- ............................................................................+0.3V to -14VInput VoltagesTIN ............................................................-0.3V to (VCC + 0.3V)RIN......................................................................................±30V
Output VoltagesTOUT ...................................................(V+ + 0.3V) to (V- - 0.3V)ROUT.........................................................-0.3V to (VCC + 0.3V)
Short-Circuit Duration, TOUT ......................................ContinuousContinuous Power Dissipation (TA = +70°C)14-Pin Plastic DIP (derate 10.00mW/°C above +70°C)....800mW16-Pin Plastic DIP (derate 10.53mW/°C above +70°C)....842mW20-Pin Plastic DIP (derate 11.11mW/°C above +70°C)....889mW24-Pin Narrow Plastic DIP
(derate 13.33mW/°C above +70°C) ..........1.07W24-Pin Plastic DIP (derate 9.09mW/°C above +70°C)......500mW16-Pin Wide SO (derate 9.52mW/°C above +70°C).........762mW
20-Pin Wide SO (derate 10 00mW/°C above +70°C).......800mW24-Pin Wide SO (derate 11.76mW/°C above +70°C).......941mW28-Pin Wide SO (derate 12.50mW/°C above +70°C) .............1W44-Pin Plastic FP (derate 11.11mW/°C above +70°C) .....889mW14-Pin CERDIP (derate 9.09mW/°C above +70°C) ..........727mW16-Pin CERDIP (derate 10.00mW/°C above +70°C) ........800mW20-Pin CERDIP (derate 11.11mW/°C above +70°C) ........889mW24-Pin Narrow CERDIP
(derate 12.50mW/°C above +70°C) ..............1W24-Pin Sidebraze (derate 20.0mW/°C above +70°C)..........1.6W28-Pin SSOP (derate 9.52mW/°C above +70°C).............762mW
Operating Temperature RangesMAX2 _ _ C _ _......................................................0°C to +70°CMAX2 _ _ E _ _ ...................................................-40°C to +85°CMAX2 _ _ M _ _ ...............................................-55°C to +125°C
Storage Temperature Range .............................-65°C to +160°CLead Temperature (soldering, 10s) .................................+300°C
ABSOLUTE MAXIMUM RATINGS—MAX223/MAX230–MAX241
ELECTRICAL CHARACTERISTICS—MAX223/MAX230–MAX241(MAX223/230/232/234/236/237/238/240/241, VCC = +5V ±10; MAX233/MAX235, VCC = 5V ±5%‚ C1–C4 = 1.0µF; MAX231/MAX239,VCC = 5V ±10%; V+ = 7.5V to 13.2V; TA = TMIN to TMAX; unless otherwise noted.)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functionaloperation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure toabsolute maximum rating conditions for extended periods may affect device reliability.
CONDITIONS MIN TYP MAX UNITS
Output Voltage Swing All transmitter outputs loaded with 3kΩ to ground ±5.0 ±7.3 V
VCC Power-Supply CurrentNo load,TA = +25°C
5 10
mA7 15
0.4 1
V+ Power-Supply Current1.8 5
mA5 15
Shutdown Supply Current TA = +25°C15 50
VInput Logic Threshold High
TIN 2.0
EN, SHDN (MAX223);EN, SHDN (MAX230/235/236/240/241)
2.4
Logic Pull-Up Current TIN = 0V 1.5 200
Receiver Input VoltageOperating Range
-30 30 V
µA
µA1 10
VInput Logic Threshold Low TIN; EN, SHDN (MAX233); EN, SHDN (MAX230/235–241) 0.8
MAX231/239
MAX223/230/234–238/240/241
MAX232/233
PARAMETER
MAX239
MAX230/235/236/240/241
MAX231
MAX223
mA
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
6 _______________________________________________________________________________________
V
0.8 1.2
PARAMETER MIN TYP MAX UNITSCONDITIONS
Normal operationSHDN = 5V (MAX223)SHDN = 0V (MAX235/236/240/241)
1.7 2.4
RS-232 Input Threshold LowTA = +25°C, VCC = 5V
0.6 1.5
VRS-232 Input Threshold HighTA = +25°C,VCC = 5V Shutdown (MAX223)
SHDN = 0V,EN = 5V (R4IN‚ R5IN)
1.5 2.4
ELECTRICAL CHARACTERISTICS—MAX223/MAX230–MAX241 (continued)(MAX223/230/232/234/236/237/238/240/241, VCC = +5V ±10; MAX233/MAX235, VCC = 5V ±5%‚ C1–C4 = 1.0µF; MAX231/MAX239,VCC = 5V ±10%; V+ = 7.5V to 13.2V; TA = TMIN to TMAX; unless otherwise noted.)
Shutdown (MAX223)SHDN = 0V,EN = 5V (R4IN, R5IN)
Normal operationSHDN = 5V (MAX223)SHDN = 0V (MAX235/236/240/241)
RS-232 Input Hysteresis VCC = 5V, no hysteresis in shutdown 0.2 0.5 1.0 V
RS-232 Input Resistance TA = +25°C, VCC = 5V 3 5 7 kΩ
TTL/CMOS Output Voltage Low IOUT = 1.6mA (MAX231/232/233, IOUT = 3.2mA) 0.4 V
TTL/CMOS Output Voltage High IOUT = -1mA 3.5 VCC - 0.4 V
TTL/CMOS Output Leakage Current0V ≤ ROUT ≤ VCC; EN = 0V (MAX223); EN = VCC (MAX235–241 )
0.05 ±10 µA
MAX223 600nsReceiver Output Enable Time
Normal operation MAX235/236/239/240/241 400
MAX223 900nsReceiver Output Disable Time
Normal operation MAX235/236/239/240/241 250
Normal operation 0.5 10
µsSHDN = 0V(MAX223)
4 40Propagation DelayRS-232 IN toTTL/CMOS OUT,CL = 150pF 6 40
3 5.1 30
V/µsMAX231/MAX232/MAX233, TA = +25°C, VCC = 5V, RL = 3kΩ to 7kΩ, CL = 50pF to 2500pF, measured from+3V to -3V or -3V to +3V
4 30
Transmitter Output Resistance VCC = V+ = V- = 0V, VOUT = ±2V 300 Ω
Transmitter Output Short-CircuitCurrent
±10 mA
tPHLS
tPLHS
Transition Region Slew Rate
MAX223/MAX230/MAX234–241, TA = +25°C, VCC = 5V, RL = 3kΩ to 7kΩ‚ CL = 50pF to 2500pF, measured from+3V to -3V or -3V to +3V
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
_______________________________________________________________________________________ 7
8.5
6.54.5 5.5
TRANSMITTER OUTPUTVOLTAGE (VOH) vs. VCC
7.0
8.0
MAX
220-
04
VCC (V)
V OH
(V)
5.0
7.5
1 TRANSMITTERLOADED
3 TRANS-MITTERSLOADED
4 TRANSMITTERSLOADED
2 TRANSMITTERSLOADED
TA = +25°CC1–C4 = 1µFTRANSMITTERLOADS =3kΩ || 2500pF
7.4
6.00 2500
TRANSMITTER OUTPUT VOLTAGE (VOH)vs. LOAD CAPACITANCE AT
DIFFERENT DATA RATES
6.4
6.2
7.2
7.0
MAX
220-
05
LOAD CAPACITANCE (pF)
V OH
(V)
15001000500 2000
6.8
6.6
160kbits/sec80kbits/sec20kbits/sec
TA = +25°CVCC = +5V3 TRANSMITTERS LOADEDRL = 3kΩC1–C4 = 1µF
12.0
4.00 2500
TRANSMITTER SLEW RATEvs. LOAD CAPACITANCE
6.0
5.0
11.0
9.0
10.0
MAX
220-
06
LOAD CAPACITANCE (pF)
SLEW
RAT
E (V
/µs)
15001000500 2000
8.0
7.0
TA = +25°CVCC = +5VLOADED, RL = 3kΩC1–C4 = 1µF
1 TRANSMITTER LOADED
2 TRANSMITTERS LOADED
3 TRANSMITTERS LOADED
4 TRANSMITTERS LOADED
-6.0
-9.04.5 5.5
TRANSMITTER OUTPUTVOLTAGE (VOL) vs. VCC
-8.0
-8.5
-6.5
-7.0
MAX
220-
07
VCC (V)
V OL (
V)
5.0
-7.5
4 TRANS-MITTERSLOADED
TA = +25°CC1–C4 = 1µFTRANSMITTERLOADS =3kΩ || 2500pF
1 TRANS-MITTERLOADED
2 TRANS-MITTERSLOADED
3 TRANS-MITTERSLOADED
-6.0
-7.60 2500
TRANSMITTER OUTPUT VOLTAGE (VOL) vs. LOAD CAPACITANCE AT
DIFFERENT DATA RATES
-7.0
-7.2
-7.4
-6.2
-6.4
MAX
220-
08
LOAD CAPACITANCE (pF)
V OL (
V)
15001000500 2000
-6.6
-6.8 160kbits/sec80kbits/sec20Kkbits/sec
TA = +25°CVCC = +5V3 TRANSMITTERS LOADEDRL = 3kΩC1–C4 = 1µF
10
-100 5 10 15 20 25 30 35 40 45 50
TRANSMITTER OUTPUT VOLTAGE (V+, V-)vs. LOAD CURRENT
-2
-6
-4
-8
8
6
MAX
220-
09
CURRENT (mA)
V+, V
- (V)
4
2
0V+ AND V-EQUALLYLOADED
V- LOADED,NO LOADON V+
TA = +25°CVCC = +5VC1–C4 = 1µF
ALL TRANSMITTERS UNLOADED
V+ LOADED,NO LOADON V-
__________________________________________Typical Operating CharacteristicsMAX223/MAX230–MAX241
*SHUTDOWN POLARITY IS REVERSED FOR NON MAX241 PARTS
V+, V- WHEN EXITING SHUTDOWN(1µF CAPACITORS)
MAX220-13
SHDN*
V-
O
V+
500ms/div
Input Logic Threshold Low
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
8 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS—MAX225/MAX244–MAX249
ELECTRICAL CHARACTERISTICS—MAX225/MAX244–MAX249(MAX225, VCC = 5.0V ±5%; MAX244–MAX249, VCC = +5.0V ±10%, external capacitors C1–C4 = 1µF; TA = TMIN to TMAX; unless oth-erwise noted.)
Note 4: Input voltage measured with transmitter output in a high-impedance state, shutdown, or VCC = 0V.Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functionaloperation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure toabsolute maximum rating conditions for extended periods may affect device reliability.
Supply Voltage (VCC) ...............................................-0.3V to +6VInput VoltagesTIN‚ ENA, ENB, ENR, ENT, ENRA,ENRB, ENTA, ENTB..................................-0.3V to (VCC + 0.3V)RIN .....................................................................................±25VTOUT (Note 3).....................................................................±15VROUT ........................................................-0.3V to (VCC + 0.3V)
Short Circuit (one output at a time)TOUT to GND............................................................ContinuousROUT to GND............................................................Continuous
Continuous Power Dissipation (TA = +70°C)28-Pin Wide SO (derate 12.50mW/°C above +70°C) .............1W40-Pin Plastic DIP (derate 11.11mW/°C above +70°C) ...611mW44-Pin PLCC (derate 13.33mW/°C above +70°C) ...........1.07W
Operating Temperature RangesMAX225C_ _, MAX24_C_ _ ..................................0°C to +70°CMAX225E_ _, MAX24_E_ _ ...............................-40°C to +85°C
Storage Temperature Range .............................-65°C to +160°CLead Temperature (soldering,10s) ..................................+300°C
VCC = 0V, VOUT = ±15V
µATables 1a–1d
±0.01 ±25
Normal operation
Shutdown
Tables 1a–1d, normal operation
All transmitter outputs loaded with 3kΩ to GND
ENA, ENB, ENT, ENTA, ENTB =VCC, VOUT = ±15V
VRS-232 Input Hysteresis
RS-232 Input Threshold Low V
V±5 ±7.5Output Voltage Swing
Output Leakage Current (Shutdown)
±0.01 ±25
Ω300 10MVCC = V+ = V- = 0V, VOUT = ±2V (Note 4)Transmitter Output Resistance
µA
PARAMETER
±0.05 ±0.10
MIN TYP MAX UNITS
Normal operation, outputs disabled,Tables 1a–1d, 0V ≤ VOUT ≤ VCC, ENR_ = VCC
TTL/CMOS Output Leakage Current
10 30Shrinking VOUT = VCCmA
-2 -10Sourcing VOUT = GND
V3.5 VCC - 0.2IOUT = -1.0mATTL/CMOS Output Voltage High
V0.2 0.4IOUT = 3.2mATTL/CMOS Output Voltage Low
kΩ3 5 7
0.2 0.5 1.0VCC = 5V
1.4 0.8 V
TTL/CMOS Output Short-Circuit Current
V1.8 2.4
0.8 1.3VCC = 5V
RS-232 Input Resistance
V±25RS-232 Input Voltage Operating Range
mA±7 ±30VOUT = 0VOutput Short-Circuit Current
kbps120 64Data Rate
CONDITIONS
VCC = 5V
µA±0.01 ±1
Logic Pull-Up/lnput Current10 50
Tables 1a–1d
RS-232 Input Threshold High
V2 1.4Input Logic Threshold High
RS-232 TRANSMITTERS
RS-232 RECEIVERS
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
_______________________________________________________________________________________ 9
Operating Supply Voltage4.75 5.25
V
Transmitter Enable Time
MAX225 10 20
tET
No loadMAX244–MAX249 11 30
5 10 30
MAX225 40VCC Supply Current (Normal Operation) 3kΩ loads on
all outputs MAX244–MAX249 57
mA
Transition Slew Rate
8 25
CL = 50pF to 2500pF, RL = 3kΩ to 7kΩ, VCC = 5V, TA = +25°C, measured from +3V to -3V or -3V to +3V
TA = TMIN to TMAX
CONDITIONS
50
V/µs
MAX246–MAX249 (excludes charge-pump startup)
Shutdown Supply Current µA
5
tPHLT 1.3 3.5
µs
tPLHT 1.5 3.5
Transmitter Disable Time, Figure 4
Transmitter Propagation DelayTLL to RS-232 (Normal Operation), Figure 1
µs
tDT 100 ns
Transmitter + to - Propagation Delay Difference (Normal Operation)
tPHLT - tPLHT
UNITSMIN TYP MAX
350
PARAMETER
ns
Receiver + to - Propagation Delay Difference (Normal Operation)
tPHLR - tPLHR 350 ns
4.5 5.5MAX244–MAX249
MAX225
Leakage current ±1
Threshold low 1.4 0.8Control Input
Threshold high 2.4 1.4V
µA
TA = +25°C
tPHLR 0.6 1.5
tPLHR 0.6 1.5
Receiver Propagation DelayTLL to RS-232 (Normal Operation),Figure 2
µs
tPHLS 0.6 10
tPLHS 3.0 10
Receiver Propagation Delay TLL to RS-232 (Low-Power Mode), Figure 2
µs
Receiver-Output Enable Time, Figure 3 tER 100 500 ns
Receiver-Output Disable Time, Figure 3 tDR 100 500 ns
MAX225/MAX245–MAX249(includes charge-pump startup)
10 ms
POWER SUPPLY AND CONTROL LOGIC
AC CHARACTERISTICS
Note 5: The 300Ω minimum specification complies with EIA/TIA-232E, but the actual resistance when in shutdown mode or VCC =0V is 10MΩ as is implied by the leakage specification.
ELECTRICAL CHARACTERISTICS—MAX225/MAX244–MAX249 (continued)(MAX225, VCC = 5.0V ±5%; MAX244–MAX249, VCC = +5.0V ±10%, external capacitors C1–C4 = 1µF; TA = TMIN to TMAX; unless oth-erwise noted.)
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
10 ______________________________________________________________________________________
__________________________________________Typical Operating Characteristics
MAX225/MAX244–MAX249
18
20 1 2 3 4 5
TRANSMITTER SLEW RATEvs. LOAD CAPACITANCE
8
6
4
16 MAX
220-
10
LOAD CAPACITANCE (nF)
TRAN
SMIT
TER
SLEW
RAT
E (V
/µs)
14
12
10
VCC = 5V
EXTERNAL POWER SUPPLY1µF CAPACITORS
40kb/s DATA RATE 8 TRANSMITTERSLOADED WITH 3kΩ
10
-100 5 10 15 20 25 30 35
OUTPUT VOLTAGEvs. LOAD CURRENT FOR V+ AND V-
-2
-4
-6
-8
8
MAX
220-
11
LOAD CURRENT (mA)
OUTP
UT V
OLTA
GE (V
)
6
4
2
0
V+ AND V- LOADEDEITHER V+ OR V- LOADED
V+ AND V- LOADED
VCC = 5VEXTERNAL CHARGE PUMP1µF CAPACITORS 8 TRANSMITTERSDRIVING 5kΩ AND2000pF AT 20kbits/sec
V- LOADED
V+ LOADED
9.0
5.00 1 2 3 4 5
TRANSMITTER OUTPUT VOLTAGE (V+, V-)vs. LOAD CAPACITANCE AT
DIFFERENT DATA RATES
6.0
5.5
8.5 MAX
220-
12
LOAD CAPACITANCE (nF)
V+, V
(V)
8.0
7.5
7.0
6.5
VCC = 5V WITH ALL TRANSMITTERS DRIVENLOADED WITH 5kΩ
10kb/sec
20kb/sec
40kb/sec
60kb/sec
100kb/sec200kb/sec
ALL CAPACITIORS 1µF
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
______________________________________________________________________________________ 11
INPUT
OUTPUT
+3V
V+
0VV-
0V
tPLHT tPHLT
tPHLRtPHLS
tPLHRtPLHS
50%VCC
50%+3V
50%INPUT
OUTPUT
*EXCEPT FOR R2 ON THE MAX243 WHERE -3V IS USED.
0V*
50%GND
Figure 1. Transmitter Propagation-Delay Timing Figure 2. Receiver Propagation-Delay Timing
EN
RX IN
a) TEST CIRCUIT
b) ENABLE TIMING
c) DISABLE TIMING
EN INPUT
RECEIVEROUTPUTS
RX OUTRX
1kΩ
0V
+3V
EN
EN
+0.8V
+3.5V
OUTPUT ENABLE TIME (tER)
VCC - 2V
VOL + 0.5V
VOH - 0.5V
OUTPUT DISABLE TIME (tDR)
VCC - 2V
+3V
0V
150pF
EN INPUT
VOH
RECEIVEROUTPUTS
VOL
1 OR 0 TX
3kΩ 50pF
-5V
+5V
OUTPUT DISABLE TIME (tDT)V+
SHDN+3V
0V
V-
0V
a) TIMING DIAGRAM
b) TEST CIRCUIT
Figure 3. Receiver-Output Enable and Disable Timing Figure 4. Transmitter-Output Disable Timing
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
12 ______________________________________________________________________________________
ENT ENR OPERATION STATUS TRANSMITTERS RECEIVERS
0 0 Normal Operation All Active All Active
0 1 Normal Operation All Active All 3-State
1 0 Shutdown All 3-State All Low-Power Receive Mode
1 1 Shutdown All 3-State All 3-State
Table 1a. MAX245 Control Pin Configurations
ENT ENROPERATION
STATUSTRANSMITTERS RECEIVERS
TA1–TA4 TB1–TB4 RA1–RA5 RB1–RB5
0 0 Normal Operation All Active All Active All Active All Active
0 1 Normal Operation All Active All ActiveRA1–RA4 3-State,RA5 Active
RB1–RB4 3-State,RB5 Active
1 0 Shutdown All 3-State All 3-StateAll Low-PowerReceive Mode
All Low-PowerReceive Mode
1 1 Shutdown All 3-State All 3-StateRA1–RA4 3-State,RA5 Low-PowerReceive Mode
RB1–RB4 3-State,RB5 Low-PowerReceive Mode
Table 1b. MAX245 Control Pin Configurations
Table 1c. MAX246 Control Pin Configurations
ENA ENBOPERATION
STATUSTRANSMITTERS RECEIVERS
TA1–TA4 TB1–TB4 RA1–RA5 RB1–RB5
0 0 Normal Operation All Active All Active All Active All Active
0 1 Normal Operation All Active All 3-State All ActiveRB1–RB4 3-State,RB5 Active
1 0 Shutdown All 3-State All ActiveRA1–RA4 3-State,RA5 Active
All Active
1 1 Shutdown All 3-State All 3-StateRA1–RA4 3-State,RA5 Low-PowerReceive Mode
RB1–RB4 3-State,RA5 Low-PowerReceive Mode
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
______________________________________________________________________________________ 13
TA1–TA4 TB1–TB4 RA1–RA4 RB1–RB4
0 0 0 0 Normal Operation All Active All Active All Active All Active
0 0 0 1 Normal Operation All Active All Active All ActiveAll 3-State, exceptRB5 stays active onMAX247
0 0 1 0 Normal Operation All Active All Active All 3-State All Active
0 0 1 1 Normal Operation All Active All Active All 3-StateAll 3-State, exceptRB5 stays active onMAX247
0 1 0 0 Normal Operation All Active All 3-State All Active All Active
0 1 0 1 Normal Operation All Active All 3-State All ActiveAll 3-State, exceptRB5 stays active onMAX247
0 1 1 0 Normal Operation All Active All 3-State All 3-State All Active
0 1 1 1 Normal Operation All Active All 3-State All 3-StateAll 3-State, exceptRB5 stays active onMAX247
1 0 0 0 Normal Operation All 3-State All Active All Active All Active
1 0 0 1 Normal Operation All 3-State All Active All ActiveAll 3-State, exceptRB5 stays active onMAX247
1 0 1 0 Normal Operation All 3-State All Active All 3-State All Active
1 0 1 1 Normal Operation All 3-State All Active All 3-StateAll 3-State, exceptRB5 stays active onMAX247
1 1 0 0 Shutdown All 3-State All 3-StateLow-PowerReceive Mode
Low-PowerReceive Mode
1 1 0 1 Shutdown All 3-State All 3-StateLow-PowerReceive Mode
All 3-State, exceptRB5 stays active onMAX247
1 1 1 0 Shutdown All 3-State All 3-State All 3-StateLow-PowerReceive Mode
1 1 1 1 Shutdown All 3-State All 3-State All 3-StateAll 3-State, exceptRB5 stays active onMAX247
Table 1d. MAX247/MAX248/MAX249 Control Pin Configurations
MAX248OPERATION
STATUSENRBMAX247 TA1–TA4 TB1–TB4 RA1–RA4 RB1–RB5
TRANSMITTERS
ENRAENTBENTA
MAX249 TA1–TA3 TB1–TB3 RA1–RA5 RB1–RB5
RECEIVERS
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The MAX220–MAX249 contain four sections: dualcharge-pump DC-DC voltage converters, RS-232 dri-vers, RS-232 receivers, and receiver and transmitterenable control inputs.
Dual Charge-Pump Voltage ConverterThe MAX220–MAX249 have two internal charge-pumpsthat convert +5V to ±10V (unloaded) for RS-232 driveroperation. The first converter uses capacitor C1 to dou-ble the +5V input to +10V on C3 at the V+ output. Thesecond converter uses capacitor C2 to invert +10V to -10V on C4 at the V- output.
A small amount of power may be drawn from the +10V(V+) and -10V (V-) outputs to power external circuitry(see the Typical Operating Characteristics section),except on the MAX225 and MAX245–MAX247, wherethese pins are not available. V+ and V- are not regulated,so the output voltage drops with increasing load current.Do not load V+ and V- to a point that violates the mini-mum ±5V EIA/TIA-232E driver output voltage whensourcing current from V+ and V- to external circuitry.
When using the shutdown feature in the MAX222,MAX225, MAX230, MAX235, MAX236, MAX240,MAX241, and MAX245–MAX249, avoid using V+ and V-to power external circuitry. When these parts are shutdown, V- falls to 0V, and V+ falls to +5V. For applica-tions where a +10V external supply is applied to the V+pin (instead of using the internal charge pump to gen-erate +10V), the C1 capacitor must not be installed andthe SHDN pin must be tied to VCC. This is because V+is internally connected to VCC in shutdown mode.
RS-232 DriversThe typical driver output voltage swing is ±8V whenloaded with a nominal 5kΩ RS-232 receiver and VCC =+5V. Output swing is guaranteed to meet the EIA/TIA-232E and V.28 specification, which calls for ±5V mini-mum driver output levels under worst-case conditions.These include a minimum 3kΩ load, VCC = +4.5V, andmaximum operating temperature. Unloaded driver out-put voltage ranges from (V+ -1.3V) to (V- +0.5V).
Input thresholds are both TTL and CMOS compatible.The inputs of unused drivers can be left unconnectedsince 400kΩ input pull-up resistors to VCC are built in(except for the MAX220). The pull-up resistors force theoutputs of unused drivers low because all drivers invert.The internal input pull-up resistors typically source 12µA,except in shutdown mode where the pull-ups are dis-abled. Driver outputs turn off and enter a high-imped-ance state—where leakage current is typicallymicroamperes (maximum 25µA)—when in shutdown
mode, in three-state mode, or when device power isremoved. Outputs can be driven to ±15V. The power-supply current typically drops to 8µA in shutdown mode.The MAX220 does not have pull-up resistors to force theoutputs of the unused drivers low. Connect unusedinputs to GND or VCC.
The MAX239 has a receiver three-state control line, andthe MAX223, MAX225, MAX235, MAX236, MAX240,and MAX241 have both a receiver three-state controlline and a low-power shutdown control. Table 2 showsthe effects of the shutdown control and receiver three-state control on the receiver outputs.
The receiver TTL/CMOS outputs are in a high-imped-ance, three-state mode whenever the three-state enableline is high (for the MAX225/MAX235/MAX236/MAX239–MAX241), and are also high-impedance whenever theshutdown control line is high.
When in low-power shutdown mode, the driver outputsare turned off and their leakage current is less than 1µAwith the driver output pulled to ground. The driver outputleakage remains less than 1µA, even if the transmitteroutput is backdriven between 0V and (VCC + 6V). Below-0.5V, the transmitter is diode clamped to ground with1kΩ series impedance. The transmitter is also zenerclamped to approximately VCC + 6V, with a seriesimpedance of 1kΩ.
The driver output slew rate is limited to less than 30V/µsas required by the EIA/TIA-232E and V.28 specifica-tions. Typical slew rates are 24V/µs unloaded and10V/µs loaded with 3Ω and 2500pF.
RS-232 ReceiversEIA/TIA-232E and V.28 specifications define a voltagelevel greater than 3V as a logic 0, so all receivers invert.Input thresholds are set at 0.8V and 2.4V, so receiversrespond to TTL level inputs as well as EIA/TIA-232E andV.28 levels.
The receiver inputs withstand an input overvoltage upto ±25V and provide input terminating resistors with
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PART SHDN EN EN(R) RECEIVERS
MAX223 __LowHighHigh
XLowHigh
High ImpedanceActiveHigh Impedance
MAX225 __ __High ImpedanceActive
__
MAX235MAX236MAX240
LowLowHigh
__ __LowHighX
High ImpedanceActiveHigh Impedance
Table 2. Three-State Control of Receivers
LowHigh
SHDN
__
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nominal 5kΩ values. The receivers implement Type 1interpretation of the fault conditions of V.28 andEIA/TIA-232E.
The receiver input hysteresis is typically 0.5V with aguaranteed minimum of 0.2V. This produces clear out-put transitions with slow-moving input signals, evenwith moderate amounts of noise and ringing. Thereceiver propagation delay is typically 600ns and isindependent of input swing direction.
Low-Power Receive ModeThe low-power receive-mode feature of the MAX223,MAX242, and MAX245–MAX249 puts the IC into shut-down mode but still allows it to receive information. Thisis important for applications where systems are periodi-cally awakened to look for activity. Using low-powerreceive mode, the system can still receive a signal thatwill activate it on command and prepare it for communi-cation at faster data rates. This operation conservessystem power.
Negative Threshold—MAX243The MAX243 is pin compatible with the MAX232A, differ-ing only in that RS-232 cable fault protection is removedon one of the two receiver inputs. This means that controllines such as CTS and RTS can either be driven or leftfloating without interrupting communication. Differentcables are not needed to interface with different pieces ofequipment.
The input threshold of the receiver without cable faultprotection is -0.8V rather than +1.4V. Its output goespositive only if the input is connected to a control linethat is actively driven negative. If not driven, it defaultsto the 0 or “OK to send” state. Normally‚ the MAX243’sother receiver (+1.4V threshold) is used for the data line(TD or RD)‚ while the negative threshold receiver is con-nected to the control line (DTR‚ DTS‚ CTS‚ RTS, etc.).
Other members of the RS-232 family implement theoptional cable fault protection as specified by EIA/TIA-232E specifications. This means a receiver output goeshigh whenever its input is driven negative‚ left floating‚or shorted to ground. The high output tells the serialcommunications IC to stop sending data. To avoid this‚the control lines must either be driven or connectedwith jumpers to an appropriate positive voltage level.
Shutdown—MAX222–MAX242 On the MAX222‚ MAX235‚ MAX236‚ MAX240‚ andMAX241‚ all receivers are disabled during shutdown.On the MAX223 and MAX242‚ two receivers continue tooperate in a reduced power mode when the chip is inshutdown. Under these conditions‚ the propagationdelay increases to about 2.5µs for a high-to-low inputtransition. When in shutdown, the receiver acts as aCMOS inverter with no hysteresis. The MAX223 andMAX242 also have a receiver output enable input (ENfor the MAX242 and EN for the MAX223) that allowsreceiver output control independent of SHDN (SHDNfor MAX241). With all other devices‚ SHDN (SHDN forMAX241) also disables the receiver outputs.
The MAX225 provides five transmitters and fivereceivers‚ while the MAX245 provides ten receivers andeight transmitters. Both devices have separate receiverand transmitter-enable controls. The charge pumpsturn off and the devices shut down when a logic high isapplied to the ENT input. In this state, the supply cur-rent drops to less than 25µA and the receivers continueto operate in a low-power receive mode. Driver outputsenter a high-impedance state (three-state mode). Onthe MAX225‚ all five receivers are controlled by theENR input. On the MAX245‚ eight of the receiver out-puts are controlled by the ENR input‚ while the remain-ing two receivers (RA5 and RB5) are always active.RA1–RA4 and RB1–RB4 are put in a three-state modewhen ENR is a logic high.
Receiver and Transmitter Enable Control Inputs
The MAX225 and MAX245–MAX249 feature transmitterand receiver enable controls.
The receivers have three modes of operation: full-speedreceive (normal active)‚ three-state (disabled)‚ and low-power receive (enabled receivers continue to functionat lower data rates). The receiver enable inputs controlthe full-speed receive and three-state modes. Thetransmitters have two modes of operation: full-speedtransmit (normal active) and three-state (disabled). Thetransmitter enable inputs also control the shutdownmode. The device enters shutdown mode when alltransmitters are disabled. Enabled receivers function inthe low-power receive mode when in shutdown.
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has no control pins and is not included in these tables.
The MAX246 has ten receivers and eight drivers withtwo control pins, each controlling one side of thedevice. A logic high at the A-side control input (ENA)causes the four A-side receivers and drivers to go intoa three-state mode. Similarly, the B-side control input(ENB) causes the four B-side drivers and receivers togo into a three-state mode. As in the MAX245, one A-side and one B-side receiver (RA5 and RB5) remainactive at all times. The entire device is put into shut-down mode when both the A and B sides are disabled(ENA = ENB = +5V).
The MAX247 provides nine receivers and eight driverswith four control pins. The ENRA and ENRB receiverenable inputs each control four receiver outputs. TheENTA and ENTB transmitter enable inputs each controlfour drivers. The ninth receiver (RB5) is always active.The device enters shutdown mode with a logic high onboth ENTA and ENTB.
The MAX248 provides eight receivers and eight driverswith four control pins. The ENRA and ENRB receiverenable inputs each control four receiver outputs. TheENTA and ENTB transmitter enable inputs control fourdrivers each. This part does not have an always-activereceiver. The device enters shutdown mode and trans-mitters go into a three-state mode with a logic high onboth ENTA and ENTB.
The MAX249 provides ten receivers and six drivers withfour control pins. The ENRA and ENRB receiver enableinputs each control five receiver outputs. The ENTAand ENTB transmitter enable inputs control three dri-vers each. There is no always-active receiver. Thedevice enters shutdown mode and transmitters go intoa three-state mode with a logic high on both ENTA andENTB. In shutdown mode, active receivers operate in alow-power receive mode at data rates up to20kbits/sec.
__________Applications InformationFigures 5 through 25 show pin configurations and typi-cal operating circuits. In applications that are sensitiveto power-supply noise, VCC should be decoupled toground with a capacitor of the same value as C1 andC2 connected as close as possible to the device.
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TOP VIEW
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
VCC
GND
T1OUT
R1INC2+
C1-
V+
C1+
MAX220MAX232
MAX232A R1OUT
T1IN
T2IN
R2OUTR2IN
T2OUT
V-
C2-
DIP/SO
V+
V-
2 +10VC1+C1
C2
1
34
5
11
10
12
9
6
14
7
13
8
T1IN
R1OUT
T2IN
R2OUT
T1OUT
R1IN
T2OUT
R2IN
+5V INPUT
C2+ -10V
C4
RS-232OUTPUTS
RS-232INPUTS
TTL/CMOSINPUTS
TTL/CMOSOUTPUTS
GND15
5kΩ
5kΩ
400kΩ
400kΩ+5V
+5V
+10V TO -10VVOLTAGE INVERTER
+5V TO +10VVOLTAGE DOUBLER
16
C3
C5
CAPACITANCE (µF)DEVICEMAX220MAX232MAX232A
C14.71.00.1
C24.71.00.1
C3101.00.1
C4101.00.1
C54.71.00.1
C2-
C1-
VCC
5kΩ
DIP/SO
18
17
16
15
14
13
12
11
1
2
3
4
5
6
7
8
SHDN
VCC
GND
T1OUTC1-
V+
C1+
(N.C.) EN
R1IN
R1OUT
T1IN
T2INT2OUT
V-
C2-
C2+
109 R2OUTR2IN
MAX222MAX242
20
19
18
17
16
15
14
13
1
2
3
4
5
6
7
8
SHDN
VCC
GND
T1OUTC1-
V+
C1+
(N.C.) EN
N.C.
R1IN
R1OUT
N.C.T2OUT
V-
C2-
C2+
12
11
9
10
T1IN
T2INR2OUT
R2IN
MAX222MAX242
SSOP
( ) ARE FOR MAX222 ONLY.PIN NUMBERS IN TYPICAL OPERATING CIRCUIT ARE FOR DIP/SO PACKAGES ONLY.
V+
V-
3 +10VC1
C2
2
45
6
12
11
13
7
15
8
14
9
T1IN
R1OUT
T2IN
R2OUT
T1OUT
(EXCEPT MAX220)
(EXCEPT MAX220)
R1IN
T2OUT
R2IN
+5V INPUT
C2+ -10V
C4
RS-232OUTPUTS
RS-232INPUTS
TTL/CMOSINPUTS
TTL/CMOSOUTPUTS
GND16
5kΩ
400kΩ
400kΩ+5V
+5V
+10V TO -10VVOLTAGE INVERTER
VCC+5V TO +10V
VOLTAGE DOUBLER
17
C3
C5
1
10
18SHDN
EN(N.C.)
ALL CAPACITORS = 0.1µF
C2-
C1+C1-
TOP VIEW
Figure 5. MAX220/MAX232/MAX232A Pin Configuration and Typical Operating Circuit
Figure 6. MAX222/MAX242 Pin Configurations and Typical Operating Circuit
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13
14
28
27
26
25
24
23
22
21
1
2
3
4
5
6
7
8
VCC
VCC VCC
400kΩ
400kΩ
400kΩ
400kΩ
400kΩ
T1OUT+5V
+5V
0.1
+5V
3
28 27
4
25
24
23
26
5
6
7
22
GNDENRENR
GND
21
+5V
+5V
+5V
T2OUT
T3OUT
T4OUT
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
1413
21
T5OUT
T5OUT
R1IN
R2IN
R3IN
R4IN
R5IN
T1IN11
12
18
17
16
15
10
9
8
19
20
T2IN
T3IN
T4IN
T5IN
ENT
R2OUT
R3OUT
R4OUT
PINS (ENR, GND, VCC, T5OUT) ARE INTERNALLY CONNECTED.CONNECT EITHER OR BOTH EXTERNALLY. T5OUT IS A SINGLE DRIVER.
R5OUT
R1OUT
VCC
ENT
T3INT2IN
T1IN
ENR
ENR
T4IN
T5IN
R4OUT
R5OUTR3IN
R3OUT
R2OUT
R1OUT
20
19
18
17
9
10
11
12
R5IN
R4IN
T3OUT
T4OUTT2OUT
T1OUT
R1IN
R2IN
SO
MAX225
16
15
T5OUT
MAX225 FUNCTIONAL DESCRIPTION5 RECEIVERS5 TRANSMITTERS2 CONTROL PINS 1 RECEIVER ENABLE (ENR) 1 TRANSMITTER ENABLE (ENT)
T5OUTGND
GND
TOP VIEW
Figure 7. MAX225 Pin Configuration and Typical Operating Circuit
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GND
10
27R3OUT
23R4OUT
R3IN
R4IN
5kΩ
5kΩ
5 4R2OUT R2IN
5kΩ
RS-232INPUTS
LOGICOUTPUTS
RS-232OUTPUTS
TTL/CMOSINPUTS
R2
8 9R1OUT R1IN
5kΩR1
R3
R4
19 18R5OUT R5IN
5kΩR5
27 T1IN T1OUT
+5V400kΩ
+5V
6 3T2IN T2OUTT2
400kΩ
20 T3OUT 1T3IN
+5V
T3
400kΩ
C1+
C1-
1.0µF
12VCC
+5V INPUT
11
17
1.0µF
131.0µF
+5V TO +10VVOLTAGE DOUBLER
26
1.0µF
T1
2821 T4IN T4OUT
+5V
400kΩ
T4
14
C2+
C2-
15
1.0µF 16+10V TO -10V
VOLTAGE INVERTER
V+
22
EN (EN)24 25
28
27
26
25
24
23
22
21
20
19
18
17
16
15
1
2
3
4
5
6
7
8
9
10
11
12
13
14
T4OUT
R3IN
R3OUT
SHDN (SHDN)
R4IN*
C2+
R4OUT*
T4IN
T3IN
R5OUT*
R5IN*
V-
C2-
C1-
V+
C1+
VCC
GND
R1IN
R1OUT
T1IN
T2IN
R2OUT
R2IN
T2OUT
T1OUT
T3OUT
Wide SO/SSOP
MAX223MAX241
EN (EN)
SHDN(SHDN)
*R4 AND R5 IN MAX223 REMAIN ACTIVE IN SHUTDOWN
NOTE: PIN LABELS IN ( ) ARE FOR MAX241
V-
TOP VIEW
Figure 8. MAX223/MAX241 Pin Configuration and Typical Operating Circuit
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20
19
18
17
16
15
14
13
1
2
3
4
5
6
7
8
T5IN
N.C.
SHDNT2IN
T2OUT
T1OUT
T5OUT
T4IN
T3IN
V-C1+
VCC
GND
T1IN
12
11
9
10
C2-
C2+C1-
V+
DIP/SO
MAX230
V+
V-
9C1+C1-
810
1112
5
4
14
13
2
3
1
20
T3IN
T4IN
T2IN
T5IN
T1OUT
T2OUT
+5V INPUT
C2+C2-
RS-232OUTPUTS
TTL/CMOSINPUTS
GND6
400kΩ+5V
400kΩ+5V
400kΩ+5V
400kΩ+5V
400kΩ+5V
+10V TO -10VVOLTAGE INVERTER
VCC+5V TO +10V
VOLTAGE DOUBLER
7
1.0µF
1.0µF
1.0µF
1.0µF
19
15
16
T3OUT T4OUT
18x
T1IN
T3OUT
T4OUT
T5OUT
17
1.0µF
T2
T3
T4
T5
N.C. SHDN
T1
TOP VIEW
Figure 9. MAX230 Pin Configuration and Typical Operating Circuit
V+
V-
14C1+
C1-
1
2
8
7
3
11
4T2IN
T1IN T1OUT
T2OUT
+5V INPUT
RS-232INPUTS
TTL/CMOSOUTPUTS
GND
12 (14)
5kΩ
5kΩ
+12V TO -12VVOLTAGE CONVERTER
13 (15)
1.0µF
1.0µFC2
1.0µF
400kΩ
+5V
400kΩ
+5V
6
9 10R1IN
R2INR2OUT
R1OUT
5
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
V+
VCC
GND
T1OUTT2OUT
V-
C-
C+
MAX231
R1IN
R1OUT
T1IN
N.C.N.C.
T2IN
R2OUT
R2IN
SO
(12)
RS-232OUTPUTS
TTL/CMOSINPUTS
(11)
(13)(10)
VCC
PIN NUMBERS IN ( ) ARE FOR SO PACKAGE
14
13
12
11
10
9
8
1
2
3
4
5
6
7
V+
VCC
GND
T1OUTT2OUT
V-
C-
C+
MAX231
R1IN
R1OUT
T1INT2IN
R2OUT
R2IN
DIP
+7.5V TO +12V
(16)
T1
T2
R1
R2
TOP VIEW
Figure 10. MAX231 Pin Configurations and Typical Operating Circuit
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2
1
5
18T2IN
T1IN T1OUT
T2OUT
+5V INPUT
RS-232OUTPUTS
TTL/CMOSOUTPUTS
GND GND6 9
400kΩ
+5V
400kΩ+5V
5kΩ
5kΩ
7
20
3 4R1IN
R2INR2OUT
R1OUT
19
RS-232OUTPUTS
TTL/CMOSINPUTS
VCC
( ) ARE FOR SO PACKAGE ONLY.
20
19
18
17
16
15
14
13
1
2
3
4
5
6
7
8
R2IN
T2OUT
V-R1IN
R1OUT
T1IN
C2-
C2+
V+ (C1-)
C1- (C1+)(V+) C1+
VCC
GND
T1OUT
12
11
9
10
V- (C2+)
C2+ (C2-)(V-) CS-
GND
DIP/SO
MAX233MAX233A
T2IN R2OUT
C1+
C1-
V-
V-
V+
C2+
C2-
C2-
C2+
8 (13)
13 (14)
12 (10)
17
14 (8)
11 (12)
15
16
10 (11)
DO NOT MAKECONNECTIONS TO
THESE PINS
INTERNAL -10POWER SUPPLY
INTERNAL +10VPOWER SUPPLY
1.0µFTOP VIEW
Figure 11. MAX233/MAX233A Pin Configuration and Typical Operating Circuit
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
T3OUT
T4OUT
T4IN
T3INT1IN
T2IN
T2OUT
T1OUT
MAX234
V-
C2-
C2+
C1-V+
C1+
VCC
GND
DIP/SO
V+
V-
8C1+
C1-
1.0µF
1.0µF
1.0µF
7
9
10
11
4
3
13
14
12
1
3
16
15
T1IN
T3IN
T2IN
T4IN
T1OUT
T3OUT
T2OUT
T4OUT
+5V INPUT
C2-
C2+
RS-232OUTPUTS
TTL/CMOSINPUTS
GND5
+5V
+5V
+10V TO -10VVOLTAGE INVERTER
VCC+5V TO +10V
VOLTAGE DOUBLER
6
+5V
+5V
400kΩ
400kΩ
400kΩ
400kΩ
1.0µF
1.0µF
T1
T2
T4
T3
TOP VIEW
Figure 12. MAX234 Pin Configuration and Typical Operating Circuit
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1.0µF+5V INPUT
GND
11
6
23
5R2OUT
RS-232INPUTS
TTL/CMOSOUTPUTS
14 13
21
R5OUT
5kΩ
17 18R4OUT
5kΩ
24R3OUT
5kΩ
24
23
22
21
20
19
18
17
1
2
3
4
5
6
7
8
R3IN
R3OUT
T5IN
SHDNT2OUT
T1OUT
T3OUT
T4OUT
EN
T5OUT
R4IN
R4OUTT1IN
T2IN
R2OUT
R2IN
16
15
14
13
9
10
11
12
T4IN
T3IN
R5OUT
R5INVCC
GND
R1IN
R1OUT
DIP
MAX235
5kΩ
9 10R1OUT R1IN
R2IN
R3IN
R4IN
R5IN
5kΩ
7
15
3
4T2IN
T3OUT RS-232OUTPUTS
TTL/CMOSINPUTS
22 19T5IN T5OUT
+5V
16 1T4IN T4OUT
+5V
2T3IN
+5V
+5V
8 T1IN T1OUT
+5V
T2OUT
T1
T1
R2
R3
R4
R5
T2
T3
T5
T4
400kΩ
400kΩ
400kΩ
400kΩ
400kΩ
SHDNEN20
12
VCC
TOP VIEW
Figure 13. MAX235 Pin Configuration and Typical Operating Circuit
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
______________________________________________________________________________________ 23
GND
8
23R2OUT RS-232INPUTS
TTL/CMOSOUTPUTS
17 16
21
R3OUT
R2IN
R3IN
5kΩ
5kΩ
5 4R1OUT R1IN
5kΩ
RS-232OUTPUTS
TTL/CMOSINPUTS
R1
R2
R3
27 T1IN T1OUT
+5V
T1
400kΩ
6 3T2IN
+5V
T2OUTT2
400kΩ
18 T3OUT 1T3IN
+5V
T3
400kΩ
19 24T4IN T4OUT
+5V
T4
400kΩ
SHDNEN20
11C1+
C1-
1.0µF
10
12
13
14
15
+5V INPUT
C2+
C2-
VCC+5V TO +10V
VOLTAGE DOUBLER
9 1.0µF
1.0µF+10V TO -10VVOLTAGE INVERTER
22
24
23
22
21
20
19
18
17
1
2
3
4
5
6
7
8
T4OUT
R2IN
R2OUT
SHDNR1IN
T2OUT
T1OUT
T3OUT
T4IN
T3IN
R3OUTGND
T1IN
T2IN
R1OUT
16
15
14
13
9
10
11
12
R3IN
V-
C2-
C2+C1-
V+
C1+
VCC
DIP/SO
MAX236 EN
1.0µF
1.0µF
TOP VIEW
V+
V-
Figure 14. MAX236 Pin Configuration and Typical Operating Circuit
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
24 ______________________________________________________________________________________
GND
8
23R2OUT RS-232INPUTS
TTL/CMOSOUTPUTS
17 16R3OUT
R2IN
R3IN
5kΩ
5kΩ
5 4R1OUT R1IN
5kΩ
RS-232OUTPUTS
TTL/CMOSINPUTS
R1
R2
R3
27 T1IN T1OUT
+5V
T1
400kΩ
6 3T2IN
+5V
T2OUTT2
400kΩ
18 T3OUT 1T3IN
+5V
T3
400kΩ
21 20T5IN T5OUT
+5V
T5
400kΩ
11C1+
C1-
1.0µF
10
12
13
14
15
+5V INPUT
C2+
C2-
VCC+5V TO +10V
VOLTAGE DOUBLER
9 1.0µF
1.0µF+10V TO -10V
VOLTAGE INVERTER
22
24
23
22
21
20
19
18
17
1
2
3
4
5
6
7
8
T4OUT
R2IN
R2OUT
T5INR1IN
T2OUT
T1OUT
T3OUT
T4IN
T3IN
R3OUTGND
T1IN
T2IN
R1OUT
16
15
14
13
9
10
11
12
R3IN
V-
C2-
C2+C1-
V+
C1+
VCC
DIP/SO
MAX237 T5OUT
1.0µF
1.0µF
19 24T4IN T4OUT
+5V
T4
400kΩ
V+
V-
TOP VIEW
Figure 15. MAX237 Pin Configuration and Typical Operating Circuit
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
______________________________________________________________________________________ 25
GND
8
3R2OUT
22 23R3OUT
R2IN
R3IN
5kΩ
5kΩ
6 7R1OUT R1IN
5kΩ
RS-232OUTPUTS
TTL/CMOSINPUTS
RS-232INPUTS
TTL/CMOSOUTPUTS
R1
R2
R3
17 16R4OUT R4IN
5kΩ
R4
25 T1IN T1OUT
+5V400kΩ
+5V
18 1T2IN T2OUTT2
400kΩ
19 T3OUT 24T3IN
+5V
T3
400kΩ
11C1+
C1-
1.0µF
10
12
13
1415
+5V INPUT
C2+
C2-
VCC+5V TO +10V
VOLTAGE DOUBLER
9 1.0µF
1.0µF+10V TO -10V
VOLTAGE INVERTER
4
1.0µF
1.0µF
21 20T4IN T4OUT
+5V
T4
400kΩ
T124
23
22
21
20
19
18
17
1
2
3
4
5
6
7
8
T3OUT
R3IN
R3OUT
T4INR2OUT
R2IN
T1OUT
T2OUT
TOP VIEW
T3IN
T2IN
R4OUTGND
R1IN
R1OUT
T1IN
16
15
14
13
9
10
11
12
R4IN
V-
C2-
C2+C1-
V+
C1+
VCC
DIP/SO
MAX238 T4OUT
V+
V-
Figure 16. MAX238 Pin Configuration and Typical Operating Circuit
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
26 ______________________________________________________________________________________
GND
3
18R3OUT
12R4OUT
R3IN
R4IN
5kΩ
5kΩ
22 21R2OUT R2IN
5kΩ
RS-232OUTPUTS
TTL/CMOSINPUTS
RS-232INPUTS
TTL/CMOSOUTPUTS
R2
1 2R1OUT R1IN
5kΩ
R1
R3
R4
10 9R5OUT R5IN
5kΩ
R5
1924 T1IN T1OUT
+5V400kΩ
+5V
23 20T2IN T2OUTT2
400kΩ
16 T3OUT 13T3IN
+5V
T3
400kΩ
C1+
C1-
1.0µF
6 VCC 8
+5V INPUT
4 5
1.0µF+10V TO -10V
VOLTAGE INVERTER
17
1.0µF
T1
24
23
22
21
20
19
18
17
1
2
3
4
5
6
7
8
T1IN
T2IN
R2OUT
R2INVCC
GND
R1IN
R1OUT
T1OUT
R3IN
R3OUTV-
C-
C+
V+
16
15
14
13
9
10
11
12
T3IN
N.C.
EN
T3OUTR4IN
R4OUT
R5OUT
R5IN
DIP/SO
MAX239 T2OUT
7.5V TO 13.2VINPUT
7
V+
11
EN14 15N.C.
V-
TOP VIEW
Figure 17. MAX239 Pin Configuration and Typical Operating Circuit
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
______________________________________________________________________________________ 27
GND
18
4R3OUT
40R4OUT
R3IN
R4IN
5kΩ
5kΩ
13 10R2OUT R2IN
5kΩ
RS-232INPUTS
TTL/CMOSOUTPUTS
RS-232OUTPUTS
TTL/CMOSINPUTS
R2
16 17R1OUT R1IN
5kΩR1
R3
R4
36 35R5OUT R5IN
5kΩ
R5
715 T1IN T1OUT
+5V400kΩ
+5V
14 8T2IN T2OUTT2
400kΩ
37 T3OUT 6T3IN
+5V
T3
400kΩ
C1+
C1-
1.0µF
25VCC
+5V INPUT
19
30
1.0µF
261.0µF
+5V TO +10VVOLTAGE DOUBLER
3
1.0µF
T1
+5V
2 41T5IN T5OUTT5
400kΩ
538 T4IN T4OUT
+5V400kΩ
T4
27
C2+
C2-
28
1.0µF 29+5V TO -10V
VOLTAGE INVERTER
V+
39
EN42 43
Plastic FP
MAX240
SHDNENT5OUTR4INR4OUT
R5OUTR5INN.C.
N.C.
T3IN
T4IN
R2OUTT2INT1IN
R1OUTR1IN
N.C.N.C.N.C.
N.C.
VCC
GND
R2IN
N.C.
T4OU
T
T2OU
TT1
OUT
T3OU
T
N.C.
R3IN
R3OU
T
N.C.
T5IN
N.C.
C1+ C2V+ C1-
C2+
N.C. V-
N.C.
N.C.
N.C.
3332313029282726252423
3435363738394041424344
1234567891011
2221201918171615141312
SHDN
TOP VIEW
V-
Figure 18. MAX240 Pin Configuration and Typical Operating Circuit
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
28 ______________________________________________________________________________________
V+
V-
2 +10VC1+
C1-
1
3
4
5
11
10
12
9
6
14
7
13
8
T1IN
R1OUT
T2IN
R2OUT
T1OUT
R1IN
T2OUT
R2IN
+5V INPUT
C2+
C2--10V
RS-232OUTPUTS
RS-232INPUTS
TTL/CMOSINPUTS
TTL/CMOSOUTPUTS
GND
15
5kΩ
5kΩ
400kΩ
400kΩ
+5V
+5V
+10V TO -10VVOLTAGE INVERTER
+5V TO +10VVOLTAGE DOUBLER
16
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
C1+ VCC
GND
T1OUT
R1IN
R1OUT
T1IN
T2IN
R2OUT
MAX243
DIP/SO
V+
C1-
V-
C2+
C2-
T2OUT
R2IN
0.1µF
0.1µF
0.1µF
0.1µFALL CAPACITORS = 0.1µF
0.1µF
RECEIVER INPUT≤ -3 VOPEN≥ +3V
R1 OUTPUTHIGHHIGHLOW
R2 OUTPUTHIGHLOWLOW
TOP VIEW
VCC
Figure 19. MAX243 Pin Configuration and Typical Operating Circuit
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
______________________________________________________________________________________ 29
400kΩ
+10V TO -10V VOLTAGE INVERTER
+5V TO +10V VOLTAGE DOUBLERVCC
400kΩ
400kΩ
GND
+5V +5V
+5V +5V
+5V
25
2423
2120
2
1µF
1µF
1µF 1µF
1µF
16
3
17
4
18
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
C2-C2+
C1-C1+
TA2OUT
TA2IN
TA3OUT
TA3IN
TA4OUT
TA4IN
9 RA1IN
10 RA1OUT
8 RA2IN
11 RA2OUT
7 RA3IN
12 RA3OUT
6 RA4IN
13 RA4OUT
5 RA5IN
14
19
RA5OUT
26
22
43
29
42
28
41
27
36
35
37
34
38
33
39
32
40
31
V-
V+
TB2OUT
TB2IN
400kΩ
2
15
TA1OUT
TA1IN
44
30
TB1OUT
TB1IN
TB3OUT
TB3IN
TB4OUT
TB4IN
RB1IN
RB1OUT
RB2IN
RB2OUT
RB3IN
RB3OUT
RB4IN
RB4OUT
RB5IN
RB5OUT
MAX249 FUNCTIONAL DESCRIPTION10 RECEIVERS 5 A-SIDE RECEIVER 5 B-SIDE RECEIVER8 TRANSMITTERS 4 A-SIDE TRANSMITTERS 4 B-SIDE TRANSMITTERSNO CONTROL PINS
441234 404142435
21 24 2625 27 2822 2319 20
8
9
10
11
12
13
14
15
16
17 29
30
31
32
33
34
35
36
37
38
TA3IN
V CC
R A5IN
MAX244
PLCC
TOP VIEWT A
4OUT
T A3O
UT
T A2O
UT
T A1O
UT
T B1O
UT
T B2O
UT
T B3O
UT
TB4O
UT
R B5IN
GND V+C1+
C2+
C1- V-C2-
T B3IN
T B4IN
RB3IN
RB2IN
RB1IN
RB1OUT
RB2OUT
RB3OUT
RB4OUT
RB5OUT
TB1IN
TB2IN
TA2IN
TA1IN
RA5OUT
RA4OUT
RA3OUT
RA2OUT
RA1OUT
RA1IN
RA2IN
7 39 RB4INRA3IN
6
18
R A4IN
T A4IN
+5V +5V
+5V +5V
Figure 20. MAX244 Pin Configuration and Typical Operating Circuit
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
30 ______________________________________________________________________________________
400kΩ
VCC
400kΩ
400kΩ
GND
+5V +5V
+5V +5V
+5V
40
17
1µF
3
18
4
19
5
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
TA2OUT
TA2IN
TA3OUT
TA3IN
TA4OUT
TA4IN
1
11 RA1IN
10 RA1OUT
12 RA2IN
9 RA2OUT
13 RA3IN
8 RA3OUT
14 RA4IN
7 RA4OUT
15 RA5IN
6
20
RA5OUT
23
37
22
36
21
35
29
30
28
31
27
32
26
33
25
34
TB2OUT
TB2IN
TB3OUT
TB3IN
TB4OUT
TB4IN
RB1IN
RB1OUT
RB2IN
RB2OUT
RB3IN
RB3OUT
RB4IN
RB4OUT
RB5IN
RB5OUT
+5V +5V
400kΩ
16
2
TA1OUT
TA1IN
24
38
TB1OUT
TB1IN
+5V +5V40 VCC
ENT
TB1IN
TB2IN
TB3IN
TB4IN
RB5OUT
RB4OUT
RB3OUT
RB2OUT
RB1OUT
RB1IN
RB2IN
RB3IN
RB4IN
RB5IN
TB1OUT
TB2OUT
TB3OUT
TB4OUT
39
38
37
36
35
34
33
32
31
1
2
3
4
5
6
7
8
9
10
ENR
TA1IN
TA2IN
TA3IN
TA4IN
RA5OUT
RA4OUT
RA3OUT
RA2OUT
RA1OUT
RA1IN
RA2IN
RA3IN
RA4IN
RA5IN
TA1OUT
TA2OUT
TA3OUT
TA4OUT
GND
TOP VIEW
MAX245
30
29
28
27
26
25
24
23
22
21
11
12
13
14
15
16
17
18
19
DIP
20
MAX245 FUNCTIONAL DESCRIPTION10 RECEIVERS 5 A-SIDE RECEIVERS (RA5 ALWAYS ACTIVE) 5 B-SIDE RECEIVERS (RB5 ALWAYS ACTIVE)8 TRANSMITTTERS 4 A-SIDE TRANSMITTERS2 CONTROL PINS 1 RECEIVER ENABLE (ENR) 1 TRANSMITTER ENABLE (ENT)
39ENR ENT
Figure 21. MAX245 Pin Configuration and Typical Operating Circuit
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
______________________________________________________________________________________ 31
400kΩ
VCC
400kΩ
GND
+5V
+5V
+5V
+5V
+5V
40
16
1µF
2
18
4
TA1OUT
TA1IN
TA3OUT
TA3IN
20
24
38
22
36
1 39
TB1OUT
TB1IN
TB3OUT
TB3IN
400kΩ
+5V17
3
TA2OUT
TA2IN
+5V23
37
TB2OUT
TB2IN
400kΩ
+5V19
5
TA4OUT
TA4IN
+5V21
35
TB4OUT
TB4IN
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
11 RA1IN
10 RA1OUT
12 RA2IN
9 RA2OUT
13 RA3IN
8 RA3OUT
14 RA4IN
7 RA4OUT
15 RA5IN
6 RA5OUT
29
30
28
31
27
32
26
33
25
34
RB1IN
RB1OUT
RB2IN
RB2OUT
RB3IN
RB3OUT
RB4IN
RB4OUT
RB5IN
RB5OUT
40 VCC
ENB
TB1IN
TB2IN
TB3IN
TB4IN
RB5OUT
RB4OUT
RB3OUT
RB2OUT
RB1OUT
RB1IN
RB2IN
RB3IN
RB4IN
RB5IN
TB1OUT
TB2OUT
TB3OUT
TB4OUT
39
38
37
36
35
34
33
32
31
1
2
3
4
5
6
7
8
9
10
ENA
TA1IN
TA2IN
TA3IN
TA4IN
RA5OUT
RA4OUT
RA3OUT
RA2OUT
RA1OUT
RA1IN
RA2IN
RA3IN
RA4IN
RA5IN
TA1OUT
TA2OUT
TA3OUT
TA4OUT
GND
TOP VIEW
MAX246
30
29
28
27
26
25
24
23
22
21
11
12
13
14
15
16
17
18
19
DIP
20
MAX246 FUNCTIONAL DESCRIPTION10 RECEIVERS 5 A-SIDE RECEIVERS (RA5 ALWAYS ACTIVE) 5 B-SIDE RECEIVERS (RB5 ALWAYS ACTIVE)8 TRANSMITTERS 4 A-SIDE TRANSMITTERS 4 B-SIDE TRANSMITTERS2 CONTROL PINS ENABLE A-SIDE (ENA) ENABLE B-SIDE (ENB)
ENA ENB
Figure 22. MAX246 Pin Configuration and Typical Operating Circuit
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
32 ______________________________________________________________________________________
400kΩ
VCC
400kΩ
GND
+5V
+5V
+5V
+5V
+5V
1
40
16
1µF
2
18
4
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
ENTA
TA1OUT
TA1IN
TA3OUT
TA3IN
6 RB5OUT
12 RA1IN
10 RA1OUT
13 RA2IN
9 RA2OUT
14 RA3IN
8 RA3OUT
15 RA4IN
7
20
RA4OUT
11
39
24
38
22
36
29
31
28
32
27
33
26
34
30ENRA
ENTB
TB1OUT
TB1IN
TB3OUT
TB3IN
RB1IN
5kΩ
25RB5IN
RB1OUT
RB2IN
RB2OUT
RB3IN
RB3OUT
RB4IN
RB4OUT
ENRB
400kΩ
+5V17
3
TA2OUT
TA2IN
+5V23
37
TB2OUT
TB2IN
400kΩ
+5V19
5
TA4OUT
TA4IN
+5V21
35
TB4OUT
TB4IN
40 VCC
ENTB
TB1IN
TB2IN
TB3IN
TB4IN
RB4OUT
RB3OUT
RB2OUT
RB1OUT
RB1IN
RB2IN
RB3IN
RB4IN
RB5IN
TB1OUT
TB2OUT
TB3OUT
TB4OUT
39
38
37
36
35
34
33
32
31
1
2
3
4
5
6
7
8
9
10
ENTA
TA1IN
TA2IN
TA3IN
TA4IN
RB5OUT
RA4OUT
RA3OUT
RA2OUT
RA1OUT
RA1IN
RA2IN
RA3IN
RA4IN
TA1OUT
TA2OUT
TA3OUT
TA4OUT
GND
TOP VIEW
MAX247
30
29
28
27
26
25
24
23
22
21
11
12
13
14
15
16
17
18
19
DIP
20
ENRA ENRB
MAX247 FUNCTIONAL DESCRIPTION9 RECEIVERS 4 A-SIDE RECEIVERS 5 B-SIDE RECEIVERS (RB5 ALWAYS ACTIVE)8 TRANSMITTERS 4 A-SIDE TRANSMITTERS 4 B-SIDE TRANSMITTERS4 CONTROL PINS ENABLE RECEIVER A-SIDE (ENRA) ENABLE RECEIVER B-SIDE (ENRB) ENABLE RECEIVER A-SIDE (ENTA) ENABLE RECEIVERr B-SIDE (ENTB)
Figure 23. MAX247 Pin Configuration and Typical Operating Circuit
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
______________________________________________________________________________________ 33
400kΩ
+10V TO -10V VOLTAGE INVERTER
+5V TO +10V VOLTAGE DOUBLERVCC
400kΩ
GND
+5V
+5V
+5V
+5V
+5V
18
25
2423
2120
1
1µF
1µF
1µF1µF
1µF
14
3
16
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
ENTA
C2-C2+
C1-C1+
TA1OUT
TA1IN
TA3OUT
TA3IN
8 RA1IN
10 RA1OUT
7 RA2IN
11 RA2OUT
6 RA3IN
12 RA3OUT
5 RA4IN
13
19
RA4OUT
9
27
26
22
44
31
42
29
37
35
38
34
39
33
40
32
36ENRA
ENTB
V-
V+
TB1OUT
TB1IN
TB3OUT
TB3IN
RB1IN
RB1OUT
RB2IN
RB2OUT
RB3IN
RB3OUT
RB4IN
RB4OUT
ENRB
400kΩ
+5V2
15
TA2OUT
TA2IN
+5V43
30
TB2OUT
TB2IN
400kΩ
+5V4
17
TA4OUT
TA4IN
+5V41
28
TB4OUT
TB4IN
441234 404142435
21 24 2625 27 2822 2319 20
8
9
10
11
12
13
14
15
16
17 29
30
31
32
33
34
35
36
37
38
TA4IN
V CC
R A4IN
MAX248
PLCC
TOP VIEWT A
4OUT
T A3O
UT
T A2O
UT
T A1O
UT
T B1O
UT
T B2O
UT
T B3O
UT
T A4O
UT
R B4IN
GND V+C1+
C2+
C1- V-C2-
T B4IN
ENTB
RB2IN
RB1IN
RB1OUT
RB2OUT
RB3OUT
RB4OUT
TB1IN
TB2IN
TB3IN
TA3IN
TA2IN
TA1IN
RA4OUT
RA3OUT
RA2OUT
RA1OUT
ENRA
RA1IN
7 39 RB3INRA2IN
6
18
R A3IN
ENRB
ENTA
MAX248 FUNCTIONAL DESCRIPTION8 RECEIVERS 4 A-SIDE RECEIVERS 4 B-SIDE RECEIVERS8 TRANSMITTERS 4 A-SIDE TRANSMITTERS 4 B-SIDE TRANSMITTERS4 CONTROL PINS ENABLE RECEIVER A-SIDE (ENRA) ENABLE RECEIVER B-SIDE (ENRB) ENABLE RECEIVER A-SIDE (ENTA) ENABLE RECEIVER B-SIDE (ENTB)
Figure 24. MAX248 Pin Configuration and Typical Operating Circuit
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
34 ______________________________________________________________________________________
400kΩ
+10V TO -10V VOLTAGE INVERTER
+5V TO +10V VOLTAGE DOUBLERVCC
400kΩ
400kΩ
GND
+5V
+5V
+5V
+5V
+5V
+5V
+5V
18
25
2423
2120
1
1µF
1µF
1µF1µF
15
2
16
3
17
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
5kΩ
ENTA
C2-C2+
C1-C1+
TA1OUT
TA1IN
TA2OUT
TA2IN
TA3OUT
TA3IN
8 RA1IN
10 RA1OUT
7 RA2IN
11 RA2OUT
6 RA3IN
12 RA3OUT
5 RA4IN
13 RA4OUT
4 RA5IN
14
19
RA5OUT
9
27
26
22
44
30
43
29
42
28
37
35
38
34
39
33
40
32
41
31
36ENRA
ENTB
V-
V+
TB1OUT
TB1IN
TB2OUT
TB2IN
TB3OUT
TB3IN
RB1IN
RB1OUT
RB2IN
RB2OUT
RB3IN
RB3OUT
RB4IN
RB4OUT
RB5IN
RB5OUT
ENRB
441234 404142435
21 24 2625 27 2822 2319 20
8
9
10
11
12
13
14
15
16
17 29
30
31
32
33
34
35
36
37
38
V CC
R A4IN
R A5IN
MAX249
PLCC
TOP VIEWT A
3OUT
T A2O
UT
T A1O
UT
T B1O
UT
T B2O
UT
T B3O
UT
R B4IN
R B5IN
GND V+C1+
C2+
C1- V-C2-
T B3IN
ENTB
RB2IN
RB1IN
RB1OUT
MAX249 FUNCTIONAL DESCRIPTION10 RECEIVERS 5 A-SIDE RECEIVERS 5 B-SIDE RECEIVERS6 TRANSMITTERS 3 A-SIDE TRANSMITTERS 3 B-SIDE TRANSMITTERS4 CONTROL PINS ENABLE RECEIVER A-SIDE (ENRA) ENABLE RECEIVER B-SIDE (ENRB) ENABLE RECEIVER A-SIDE (ENTA) ENABLE RECEIVER B-SIDE (ENTB)
RB2OUT
RB3OUT
RB4OUT
RB5OUT
TB1IN
TB2INTA3IN
TA2IN
TA1IN
RA4OUT
RA5OUT
RA3OUT
RA2OUT
RA1OUT
ENRA
RA1IN
7 39 RB3INRA2IN
6
18
R A3IN
ENRB
ENTA
1µF
Figure 25. MAX249 Pin Configuration and Typical Operating Circuit
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers
______________________________________________________________________________________ 35
___________________________________________Ordering Information (continued)
PART
MAX222CPN 0°C to +70°C
TEMP RANGE PIN-PACKAGE PART TEMP RANGE PIN-PACKAGE
18 Plastic DIP
MAX222CWN 0°C to +70°C 18 Wide SO
MAX222C/D 0°C to +70°C Dice*
MAX222EPN -40°C to +85°C 18 Plastic DIP
MAX222EWN -40°C to +85°C 18 Wide SO
MAX222EJN -40°C to +85°C 18 CERDIP
MAX222MJN -55°C to +125°C 18 CERDIP
MAX223CAI 0°C to +70°C 28 SSOP
MAX223CWI 0°C to +70°C 28 Wide SO
MAX223C/D 0°C to +70°C Dice*
MAX223EAI -40°C to +85°C 28 SSOP
MAX223EWI -40°C to +85°C 28 Wide SO
MAX225CWI 0°C to +70°C 28 Wide SO
MAX225EWI -40°C to +85°C 28 Wide SO
MAX230CPP 0°C to +70°C 20 Plastic DIP
MAX230CWP 0°C to +70°C 20 Wide SO
MAX230C/D 0°C to +70°C Dice*
MAX230EPP -40°C to +85°C 20 Plastic DIP
MAX230EWP -40°C to +85°C 20 Wide SO
MAX230EJP -40°C to +85°C 20 CERDIP
MAX230MJP -55°C to +125°C 20 CERDIP
MAX231CPD 0°C to +70°C 14 Plastic DIP
MAX231CWE 0°C to +70°C 16 Wide SO
MAX231CJD 0°C to +70°C 14 CERDIP
MAX231C/D 0°C to +70°C Dice*
MAX231EPD -40°C to +85°C 14 Plastic DIP
MAX231EWE -40°C to +85°C 16 Wide SO
MAX231EJD -40°C to +85°C 14 CERDIP
MAX231MJD -55°C to +125°C 14 CERDIP
MAX232CPE 0°C to +70°C 16 Plastic DIP
MAX232CSE 0°C to +70°C 16 Narrow SO
MAX232CWE 0°C to +70°C 16 Wide SO
MAX232C/D 0°C to +70°C Dice*
MAX232EPE -40°C to +85°C 16 Plastic DIP
MAX232ESE -40°C to +85°C 16 Narrow SO
MAX232EWE -40°C to +85°C 16 Wide SO
MAX232EJE -40°C to +85°C 16 CERDIP
MAX232MJE -55°C to +125°C 16 CERDIP
MAX232MLP -55°C to +125°C 20 LCC
MAX232ACPE 0°C to +70°C 16 Plastic DIP
MAX232ACSE 0°C to +70°C 16 Narrow SO
MAX232ACWE 0°C to +70°C 16 Wide SO
MAX232AC/D
MAX232AEPE -40°C to +85°C 16 Plastic DIP
MAX232AESE
0°C to +70°C Dice*
-40°C to +85°C 16 Narrow SO
MAX232AEWE -40°C to +85°C 16 Wide SO
MAX232AEJE -40°C to +85°C 16 CERDIP
MAX232AMJE -55°C to +125°C 16 CERDIP
MAX232AMLP -55°C to +125°C 20 LCC
MAX233CPP 0°C to +70°C 20 Plastic DIP
MAX233EPP -40°C to +85°C 20 Plastic DIP
MAX233ACPP 0°C to +70°C 20 Plastic DIP
MAX233ACWP 0°C to +70°C 20 Wide SO
MAX233AEPP -40°C to +85°C 20 Plastic DIP
MAX233AEWP -40°C to +85°C 20 Wide SO
MAX234CPE 0°C to +70°C 16 Plastic DIP
MAX234CWE 0°C to +70°C 16 Wide SO
MAX234C/D 0°C to +70°C Dice*
MAX234EPE -40°C to +85°C 16 Plastic DIP
MAX234EWE -40°C to +85°C 16 Wide SO
MAX234EJE -40°C to +85°C 16 CERDIP
MAX234MJE -55°C to +125°C 16 CERDIP
MAX235CPG 0°C to +70°C 24 Wide Plastic DIP
MAX235EPG -40°C to +85°C 24 Wide Plastic DIP
MAX235EDG -40°C to +85°C 24 Ceramic SB
MAX235MDG -55°C to +125°C 24 Ceramic SB
MAX236CNG 0°C to +70°C 24 Narrow Plastic DIP
MAX236CWG 0°C to +70°C 24 Wide SO
MAX236C/D 0°C to +70°C Dice*
MAX236ENG -40°C to +85°C 24 Narrow Plastic DIP
MAX236EWG -40°C to +85°C 24 Wide SO
MAX236ERG -40°C to +85°C 24 Narrow CERDIP
MAX236MRG -55°C to +125°C 24 Narrow CERDIP
MAX237CNG 0°C to +70°C 24 Narrow Plastic DIP
MAX237CWG 0°C to +70°C 24 Wide SO
MAX237C/D 0°C to +70°C Dice*
MAX237ENG -40°C to +85°C 24 Narrow Plastic DIP
MAX237EWG -40°C to +85°C 24 Wide SO
MAX237ERG -40°C to +85°C 24 Narrow CERDIP
MAX237MRG -55°C to +125°C 24 Narrow CERDIP
MAX238CNG 0°C to +70°C 24 Narrow Plastic DIP
MAX238CWG 0°C to +70°C 24 Wide SO
MAX238C/D 0°C to +70°C Dice*
MAX238ENG -40°C to +85°C 24 Narrow Plastic DIP
* Contact factory for dice specifications.
MA
X2
20
–MA
X2
49
+5V-Powered, Multichannel RS-232Drivers/Receivers___________________________________________Ordering Information (continued)
* Contact factory for dice specifications.
18 CERDIP-55°C to +125°CMAX242MJN
18 CERDIP-40°C to +85°CMAX242EJN
18 Wide SO-40°C to +85°CMAX242EWN
18 Plastic DIP-40°C to +85°CMAX242EPN
Dice*0°C to +70°CMAX242C/D
18 Wide SO0°C to +70°CMAX242CWN
18 Plastic DIP0°C to +70°CMAX242CPN
20 SSOP0°C to +70°CMAX242CAP
28 Wide SO-40°C to +85°CMAX241EWI
28 SSOP-40°C to +85°CMAX241EAI
Dice*0°C to +70°CMAX241C/D
28 Wide SO0°C to +70°CMAX241CWI
28 SSOP0°C to +70°CMAX241CAI
Dice*0°C to +70°CMAX240C/D
44 Plastic FP0°C to +70°CMAX240CMH
24 Narrow CERDIP-55°C to +125°CMAX239MRG
24 Narrow CERDIP-40°C to +85°CMAX239ERG
24 Wide SO-40°C to +85°CMAX239EWG
24 Narrow Plastic DIP-40°C to +85°CMAX239ENG
Dice*0°C to +70°CMAX239C/D
24 Wide SO0°C to +70°CMAX239CWG
24 Narrow Plastic DIP0°C to +70°CMAX239CNG
24 Narrow CERDIP-55°C to +125°C
24 Wide SO
PIN-PACKAGETEMP RANGE
-40°C to +85°C
MAX238MRG
24 Narrow CERDIP-40°C to +85°CMAX238ERG
MAX238EWG
PART PIN-PACKAGETEMP RANGEPART
44 PLCC-40°C to +85°CMAX249EQH
44 PLCC0°C to +70°CMAX249CQH
44 PLCC-40°C to +85°CMAX248EQH
Dice*0°C to +70°CMAX248C/D
44 PLCC0°C to +70°CMAX248CQH
40 Plastic DIP-40°C to +85°CMAX247EPL
Dice*0°C to +70°CMAX247C/D
40 Plastic DIP0°C to +70°CMAX247CPL
40 Plastic DIP-40°C to +85°CMAX246EPL
Dice*0°C to +70°CMAX246C/D
40 Plastic DIP0°C to +70°CMAX246CPL
40 Plastic DIP-40°C to +85°CMAX245EPL
Dice*0°C to +70°CMAX245C/D
40 Plastic DIP0°C to +70°CMAX245CPL
44 PLCC-40°C to +85°CMAX244EQH
Dice*0°C to +70°CMAX244C/D
44 PLCC0°C to +70°CMAX244CQH
16 CERDIP-55°C to +125°CMAX243MJE
16 CERDIP-40°C to +85°CMAX243EJE
16 Wide SO-40°C to +85°CMAX243EWE
16 Narrow SO-40°C to +85°CMAX243ESE
16 Plastic DIP-40°C to +85°CMAX243EPE
Dice*0°C to +70°CMAX243C/D
16 Wide SO0°C to +70°C
16 Plastic DIP0°C to +70°C
MAX243CWE
16 Narrow SO0°C to +70°CMAX243CSE
MAX243CPE
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses areimplied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
36 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600
© 2003 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
Package InformationFor the latest package outline information, go towww.maxim-ic.com/packages.
ANEXO A.3 – MX7828
_______________General DescriptionThe MAX154/MAX158 and MX7824/MX7828 are high-speed, multi-channel analog-to-digital converters(ADCs). The MAX154 and MX7824 have four analoginput channels, while the MAX158 and MX7828 haveeight channels. Conversion time for all devices is 2.5µs.The MAX154/MAX158 also feature a 2.5V on-chip refer-ence, forming a complete high-speed data acquisitionsystem.
All four converters include a built-in track/hold, eliminat-ing the need for an external track/hold with many inputsignals. The analog input range is 0V to +5V, althoughthe ADC operates from a single +5V supply.
Microprocessor interfaces are simplified by the ADC’sability to appear as a memory location or I/O port withoutthe need for external logic. The data outputs use latched,three-state buffer circuitry to allow direct connection to amicroprocessor data bus or system input port.
The MX7824 and MX7828 are pin compatible withAnalog Devices’ AD7824 and AD7828. The MAX154and MAX158, which feature internal references, are alsocompatible with these products.
________________________ApplicationsDigital Signal ProcessingHigh-Speed Data AcquisitionTelecommunicationsHigh-Speed Servo ControlAudio Instrumentation
____________________________Features♦ One-Chip Data Acquisition System
♦ Four or Eight Analog Input Channels
♦ 2.5µs per Channel Conversion Time
♦ Internal 2.5V Reference (MAX154/MAX158 only)
♦ Built-In Track/Hold Function
♦ 1/2LSB Error Specification
♦ Single +5V Supply Operation
♦ No External Clock
♦ New Space-Saving SSOP Package
______________Ordering Information
MX
78
24
/MX
78
28
CMOS, High-Speed, 8-Bit ADCs with Multiplexer
________________________________________________________________ Maxim Integrated Products 1
24
23
22
21
20
19
18
17
1
2
3
4
5
6
7
8
VDD
NC
A0
A1AIN1
AIN2
AIN3
AIN4
TOP VIEW
DB7
( ) ARE FOR MAX154/MAX158 ONLY.
DB6
DB5
DB4DB2
DB1
DB0
TP (REF OUT)
16
15
14
13
9
10
11
12
CS
RDY
VREF+
VREF-GND
INT
RD
DB3
DIP/SO/SSOP
MAX154 MX7824
28
27
26
25
24
23
22
21
1
2
3
4
5
6
7
8
AIN7
AIN8
VDD
A0AIN3
AIN4
AIN5
AIN6
A1
A2
DB7
DB6DB0
TP (REF OUT)
AIN1
AIN2
20
19
18
17
9
10
11
12
DB5
DB4
CS
RDYRD
DB3
DB2
DB1
DIP/SO/SSOP
MAX158 MX7828
16
15
13
14
VREF+
VREF-GND
INT
__________________________________________________________Pin Configurations
Call toll free 1-800-998-8800 for free samples or literature.
19-0255; Rev 2; 4/94
PART
MX7824LN
MX7824KN
MX7824LCWG 0°C to +70°C
0°C to +70°C
0°C to +70°C
TEMP. RANGE PIN-PACKAGE
24 NarrowPlastic DIP
24 NarrowPlastic DIP
24 Wide SO
MX7824KCWG
MX7824LCAG
MX7824KCAG 0°C to +70°C
0°C to +70°C
0°C to +70°C 24 Wide SO
24 SSOP
24 SSOP
Ordering Information continued on last page.
ERROR(LSB)
±1/2
±1
±1/2±1
±1/2±1
MX
78
24
/MX
78
28
CMOS, High-Speed, 8-Bit ADCs with Multiplexer
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS(VDD = +5V, VREF+ = +5V, VREF- = GND, Mode 0, TA = TMIN to TMAX, unless otherwise noted.)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functionaloperation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure toabsolute maximum rating conditions for extended periods may affect device reliability.
Supply Voltage, VDD to GND........................................0V, +10VVoltage at Any Other Pins......................GND - 0.3V, VDD + 0.3VOutput Current (REF OUT)..................................................30mAPower Dissipation (any package) to +75°C ....................450mW
Derate above +25°C by ..............................................6mW/°C
Operating Temperature RangesMX7824, MX7828
KN/LN/KCW_/LCW_............................................0°C to +70°CBQ/CQ .............................................................-40°C to +85°CTQ/UQ............................................................-55°C to +125°C
Storage Temperature Range .............................-65°C to +160°CLead Temperature (soldering, 10sec) .............................+300°C
Input Capacitance (Note 4) CIN 5 8 pF
Input Low Voltage VINL 0.8 V
Input High Current IINH 1 µA
Input Low Current IINL -1 µA
Analog Input Current IAIN ±3 µA
Slew Rate, Tracking SR 0.7 0.157 V/µs
Input High Voltage VINH 2.4 V
Any channel, AIN = 0V to 5V
Output Noise eN 200 µV/rms
Capacitive Load 0.01 µF
Analog Input Voltage Range AINR VREF- VREF+ V
Analog Input Capacitance CAIN 45 pF
±1MAX15_B, MX782_K/B/T
PARAMETER SYMBOL MIN TYP MAX UNITS
Channel to Channel Mismatch ±1/4 LSB
No Missing Codes Resolution 8 Bits
Total Unadjusted Error (Note 1)±1/2
LSB
Reference Resistance 1 4 kΩVREF+ Input Voltage Range VREF- VDD V
VREF- Input Voltage Range GND VREF+ V
Resolution 8 Bits
Output Voltage REF OUT 2.47 2.50 2.53 V
Load Regulation -6 -10 mV
Power-Supply Sensitivity ±1 ±3 mV
40 70
40 70Temperature Drift (Note 3)
60 100
ppm/°C
CONDITIONS
TA = +25°C
IL = 0mA to 10mA, TA = +25°C
MAX15_A, MX782_L/C/U
VDD ±5%, TA = +25°C
MAX15_C
MAX15_E
MAX15_M
ACCURACY
REFERENCE INPUT
REFERENCE OUTPUT—MAX154/MAX158 Only (Note 2)
ANALOG INPUT
LOGIC INPUTS (–R—D–, –C—S–, A0, A1, A2)
ELECTRICAL CHARACTERISTICS(VDD = +5V, VREF+ = +5V, VREF- = GND, Mode 0, TA = TMIN to TMAX, unless otherwise noted.)
TIMING CHARACTERISTICS (Note 5)(VDD = +5V, VREF+ = +5V, VREF- = GND, Mode 0, TA = TMIN to TMAX, unless otherwise noted.)
Note 1: Total unadjusted error includes offset, full-scale, and linearity errors.Note 2: Specified with no external load unless otherwise noted.Note 3: Temperature drift is defined as change in output voltage from +25°C to TMIN or TMAX divided by (25 - TMIN) or (TMAX - 25).Note 4: Guaranteed by design.
Note 5: All input control signals are specified with tR = tF = 20ns (10% to 90% of +5V) and timed from a 1.6V voltage level.Note 6: Measured with load circuits of Figure 1 and defined as the time required for an output to cross 0.8V or 2.4V.Note 7: Defined as the time required for the data lines to change 0.5V when loaded with the circuits of Figure 2.
MX
78
24
/MX
78
28
CMOS, High-Speed, 8-Bit ADCs with Multiplexer
_______________________________________________________________________________________ 3
(Note 6)
(Note 6)
CL = 50pF, RL = 5kΩ
(Note 7)
CL = 50pF
CONDITIONS
ns60tDHData Hold Time
ns40 75tINTH–R—D– to –I—N—T– Delay (Mode 1)
ns0tCSH
ns0tCSS–C—S– to –R—D– Setup Time–C—S– to –R—D– Hold Time
ns20 50tACC2Data Access TimeAfter –I—N—T–, Mode 0
ns85tACC1Data Access Time After –R—D–µs1.6 2.0tCRDConversion Time (Mode 0)ns30 40tRDY
–C—S– to RDY Delay
ns0tASMultiplexer AddressSetup Time
ns30tAHMultiplexer AddressHold Time
UNITSTA = +25°C
SYMBOLPARAMETER
ns500tPDelay TimeBetween Conversions
500
70
100
0
0
60
1102.460
0
35
MAX15_ _C/EMX782_K/L/B/C
600
70
100
0
0
70
1202.860
0
40
MAX15_ _MMX782_T/U
MIN MAX MIN MAXMIN TYP MAX
ns60 600tRD–R—D– Pulse Width (Mode 1) 80 500 80 400
DB0–DB7, –I—N—T–; IOUT = -360µA
–C—S– = –R—D– = 2.4V
5V ±5% for specified performance
DB0–DB7, RDY; VOUT = 0V to VDD
VDD = ±5%
CONDITIONS
LSB±1/16 ±1/4PSSPower-Supply Sensitivity
V4.0VOHOutput High Voltage
mW25 75Power Dissipation
mA15IDDSupply Current
V4.75 5.25VDDSupply Voltage
µA±3Three-State Output Current
pF5 8COUTOutput Capacitance (Note 4)
UNITSMIN TYP MAXSYMBOLPARAMETER
DB0–DB7, –I—N—T–; RDY0.4
V0.4
VOLOutput Low VoltageIOUT = 1.6mA
IOUT = 2.6mA
LOGIC OUTPUTS
POWER SUPPLY
MX
78
24
/MX
78
28
CMOS, High-Speed, 8-Bit ADCs with Multiplexer
4 _______________________________________________________________________________________
__________________________________________Typical Operating Characteristics(TA = +25°C, unless otherwise noted.)
2.520
2.480-50 150
REFERENCE TEMPERATURE
DRIFT (MAX154/MAX158 ONLY)
2.490
2.510
MX7
824/
28-1
AMBIENT TEMPERATURE (°C)
REF
OUT
VOLT
AGE
(V)
2.500
1000 50
20
0-100 150
OUTPUT CURRENT vs. TEMPERATURE
4
12
16
MX7
824/
28-2
AMBIENT TEMPERATURE (°C)
OUTP
UT C
URRE
NT (m
A)
8
100-50 0 50
VDD = 5V
ISOURCE VOUT = 2.4V
ISINK VOUT = 0.4V
2.0
0300 900
ACCURACY vs. DELAY BETWEEN CONVERSIONS (tp)
0.5
1.0
1.5
MX7
824/
28-3
tp (ns)
LINE
ARIT
Y ER
ROR
(LSB
)
700 800400 500 600
VDD = 5V VREF = 5V
2.0
00 5
ACCURACY vs. VREF
(VREF = VREF+ - VREF-)
0.5
1.0
1.5
MX7
824/
28-4
VREF (V)
LINE
ARIT
Y ER
ROR
(LSB
)
3 41 2
VDD = 5V
3k
3k
100pF
DGND
DBN
a. High-Z to VOH b. High-Z to VOL
DBN
+5V
DGND
100pF 3k
3k
10pF
DGND
DBN
a. VOH to High-Z b. VOL to High-Z
DBN
+5V
DGND
10pF
8
2-100 150
POWER-SUPPLY CURRENT vs. TEMPERATURE
(NOT INCLUDING REFERENCE LADDER)
3
4
5
6
7 MX7
824/
28-5
AMBIENT TEMPERATURE (°C)
I DD
– SU
PPLY
CUR
RENT
(mA)
50 100-50 0
VDD = 5.25V
VDD = 5V
VDD = 4.75V
Figure 1. Load Circuits for Data-Access Time Test Figure 2. Load Circuits for Data-Hold Time Test
MX
78
24
/MX
78
28
CMOS, High-Speed, 8-Bit ADCs with Multiplexer
_______________________________________________________________________________________ 5
Reference Output (2.5V) for MAX154.Test point for MX7824. Do not connect.
REF OUTTP
5
Three-State Data Output, bit 0 (LSB)DBO6
Three-State Data Output, bit 1DB17
Analog Input Channel 1AIN14
Analog Input Channel 2AIN23
PIN
Analog Input Channel 3AIN32
Analog Input Channel 4AIN41
FUNCTIONNAME
_____________________________________________________________Pin Descriptions
Three-State Data Output, bit 2DB28
Three-State Data Output, bit 3DB39
Read Input. –R—D– controls conversionsand data access. See Digital Interfacesection.
–R—D–10
Three-State Data Output, bit 7 (MSB)DB720
GroundGND12Lower Limit of Reference Span. Setsthe zero-code voltage. Range: GND to VREF+.
VREF-13
Interrupt Output. INT going low indi-cates the completion of a conversion.See Digital Interface section.
INT11
Chip-Select Input. –C—S– must be low forthe device to be selected.
–C—S–16
Three-State Data Output, bit 4DB417
Three-State Data Output, bit 5DB518
Three-State Data Output, bit 6DB619
Interrupt Output. INT going low indi-cates the completion of a conversion.See Digital Interface section.
INT13
GroundGND14
Analog Input Channel 2AIN25
Analog Input Channel 1AIN16
Reference Output (2.5V) for MAX158. Test point for MX7828. Do not connect.
REF OUTTP
7
Analog Input Channel 3AIN34
Analog Input Channel 4AIN43
PIN
Analog Input Channel 5AIN52
Analog Input Channel 6AIN61
FUNCTIONNAME
Three-State Data Output, bit 0 (LSB)DB08
Three-State Data Output, bit 1DB19
Three-State Data Output, bit 2DB210
Three-State Data Output, bit 3DB311
Lower Limit of Reference Span. Setsthe zero-code voltage. Range: GND to VREF+.
VREF-15
Read Input. –R—D– controls conversionsand data access. See Digital Interfacesection.
–R—D–12
Ready Output. Open-drain output withno active pull-up device. Goes lowwhen –C—S– goes low and high imped-ance at the end of a conversion.
RDY17
Power-Supply Voltage, +5VVDD26
Channel Address 2 InputA223
Channel Address 1 InputA124
Channel Address 0 InputA025
Upper Limit of Reference Span. Sets the full-scale input voltage. Range: VREF- to VDD.
VREF+14
Ready Output. Open-drain output withno active pull-up device. Goes lowwhen –C—S– goes low and high imped-ance at the end of a conversion.
RDY15
Power-Supply Voltage, +5VVDD24
Channel Address 1 InputA121
Channel Address 0 InputA022
No ConnectNC23
Three-State Data Output, bit 7 (MSB)DB722
Chip-Select Input. –C—S– must be low forthe device to be selected.
–C—S–18
Three-State Data Output, bit 4DB419
Three-State Data Output, bit 5DB520
Three-State Data Output, bit 6DB621
Analog Input Channel 8AIN827
Analog Input Channel 7AIN728
Upper Limit of Reference Span. Setsthe full-scale input voltage. Range: VREF- to VDD.
VREF+16
MAX154MX7824
MAX158MX7828
MX
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24
/MX
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28
CMOS, High-Speed, 8-Bit ADCs with Multiplexer
6 _______________________________________________________________________________________
_______________Detailed DescriptionConverter Operation
The MAX154/MAX158 and MX7824/MX7828 use what iscommonly called a “half-flash” conversion technique(Figure 3). Two 4-bit flash ADC sections are used toachieve an 8-bit result. Using 15 comparators, theupper 4-bit MS (most significant) flash ADC comparesthe unknown input voltage to the reference ladder andprovides the upper four data bits.
An internal DAC uses the MS bits to generate an analogsignal from the first flash conversion. A residue voltagerepresenting the difference between the unknown inputand the DAC voltage is then compared to the referenceladder by 15 LS (least significant) flash comparators toobtain the lower four output bits.
Operating SequenceThe operating sequence is shown in Figure 4. A con-version is initiated by a falling edge of RD and CS. Thecomparator inputs track the analog input voltage forapproximately 1µs. After this first cycle, the MS flashresult is latched into the output buffers and the LS con-version begins. INT goes low approximately 600nslater, indicating the end of the conversion, and that thelower four bits are latched into the output buffers. Thedata can then be accessed using the CS and RDinputs.
___________________Digital InterfaceThe MAX154/MAX158 and MX7824/MX7828 use onlyChip Select (CS) and Read (RD) as control inputs. AREAD operation, taking CS and RD low, latches the mul-tiplexer address inputs and starts a conversion (Table 1).
There are two interface modes, which are determinedby the length of the RD input. Mode 0, implemented bykeeping RD low until the conversion ends, is designedfor microprocessors that can be forced into a WAITstate. In this mode, a conversion is started with a READoperation (taking CS and RD low), and data is readwhen the conversion ends. Mode 1, on the other hand,
4-BIT DAC
THREE- STATE
DRIVERS
ADDRESS LATCH
DECODE
4-BIT FLASH ADC
(4LSB)
4-BIT FLASH ADC
(4MSB)
2.5V REF
TIMING AND CONTROL CIRCUITRY
MUX*
VREF+
VREF+16
A0*MAX154/MX7824 – 4-Channel Mux MAX158/MX7828 – 8-Channel Mux** REF OUT on MAX154/MAX158 only
A1 A2 RDY CS RD
AIN1
AIN4
AIN8
REF OUT**
VREF-
DB7DB6DB5
DB4
DB3DB2DB1
DB0
INT
MAX154/MX7824A1 A0
MAX158/MX7828A2 A1 A0
SELECTEDCHANNEL
0 00 11 01 1
0 0 00 0 10 1 00 1 1
AIN1AIN2AIN3AIN4
Figure 3. Functional Diagram
Table 1. Truth Table for Input ChannelSelection
1 0 01 0 11 1 01 1 1
AIN5AIN6AIN7AIN8
does not require microprocessor WAIT states. A READoperation simultaneously initiates a conversion andreads the previous conversion result.
Interface Mode 0Figure 5 shows the timing diagram for Mode 0 opera-tion. This is used with microprocessors that have WAITstate capability, whereby a READ instruction is extend-ed to accommodate slow-memory devices. Taking CSand RD low latches the analog multiplexer address andstarts a conversion. Data outputs DB0–DB7 remain inthe high-impedance condition until the conversion iscomplete.
There are two status outputs: Interrupt (INT) and Ready(RDY). RDY, an open-drain output (no internal pull-updevice), is connected to the processor’s READY/WAITinput. RDY goes low on the falling edge of CS and goeshigh impedance at the end of the conversion, when theconversion result appears on the data outputs. If the RDYoutput is not required, its external pull-up resistor can beomitted. INT goes low when the conversion is completeand returns high on the rising edge of CS or RD.
Interface Mode 1Mode 1 is designed for applications where the micro-processor is not forced into a WAIT state. Taking CSand RD low latches the multiplexer address and startsa conversion (Figure 6). Data from the previous conver-sion is immediately read from the outputs (DB0–DB7).
INT goes high at the rising edge of CS or RD and goeslow at the end of the conversion. A second READ oper-ation is required to read the result of this conversion.The second READ latches a new multiplexer addressand starts another conversion. A delay of 2.5µs mustbe allowed between READ operations. RDY goes lowon the falling edge of CS and goes high impedance atthe rising edge of CS. If RDY is not needed, its externalpull-up resistor can be omitted.
MX
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CMOS, High-Speed, 8-Bit ADCs with Multiplexer
_______________________________________________________________________________________ 7
500ns
VIN IS TRACKED BY INTERNAL COMPARATORS
VIN IS SAMPLED AND THE FOUR MSBs ARE LATCHED
SETUP TIME REQUIRED BY THE INTERNAL COMPARATORS PRIOR TO STARTING CONVERSION
600ns
RD
INT GOING LOW INDICATES THAT CONVERSION IS COMPLETE AND THAT DATA CAN BE READ
1000ns
Figure 4. Operating Sequence
DATA DATA VALID
ADDR VALID
ADDR VALID
INT
RDY
RD
ANALOG CHANNEL ADDRESS
CS
tAS
tAH
tRDY
tCRD
HIGH IMPEDANCE
tCSS tCSS
tINTH
tDHtACC2
tAS
tP
tCSH
Figure 5. Mode 0 Timing Diagram
MX
78
24
/MX
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28
_____________Analog ConsiderationsReference and Input
The VREF+ and VREF- inputs of the converter define thezero and the full-scale of the ADC. In other words, thevoltage at VREF- is equal to the input voltage that pro-duces an output code of all zeros, and the voltage atVREF+ is equal to input voltage that produces an outputcode of all ones (Figure 7).
Figure 8 shows some possible reference configura-tions. For the MAX154/MAX158, a 0.01µF bypasscapacitor to GND should be used to reduce the high-frequency output impedance of the internal reference.Larger capacitors should not be used, as this degradesthe stability of the reference buffer. The 2.5V referenceoutput is with respect to the GND pin.
BypassingA 47µF electrolytic and 0.1µF ceramic capacitor shouldbe used to bypass the VDD pin to GND. These capaci-tors must have minimum lead length, since excess leadlength may contribute to conversion errors and instability. If the reference inputs are driven by long lines, theyshould be bypassed to GND with 0.1µF capacitors atthe reference input pins.
CMOS, High-Speed, 8-Bit ADCs with Multiplexer
8 _______________________________________________________________________________________
DATA NEW DATA
ADDR VALID
INT
RDY
RD
ANALOG CHANNEL ADDRESS
CS
tAS
tAH
tRDY
tACCI
tCRD
tRDtCSS tRD
tRDY
tINTH
tDH
tAH
tINTH
tAS
tP
tCSStCSH
ADDR VALID
OLD DATA
tDH
tCSH
tACCI
Figure 6. Mode 1 Timing Diagram
11111111
11111110
11111101
00000011
00000010
00000001
000000001
VREF-2 3 FS
VREF+
FS–1LSB
OUTPUT CODE
FULL-SCALE TRANSITION
1LSB = F8 = VREF+ - VREF- 256 256
AIN INPUT VOLTAGE (IN TERMS OF LSBs)
Figure 7. Transfer Function
Input CurrentThe converters’ analog inputs behave somewhat differ-ently from conventional ADCs. The sampled data com-parators take varying amounts of current from the input,depending on the cycle they are in. The equivalent cir-cuit of the converter is shown in Figure 9a. When theconversion starts, AIN(n) is connected to the MS andLS comparators. Thus, AIN(n) is connected to thirty-one1pF capacitors.
To acquire the input signal in approximately 1µs, theinput capacitors must charge to the input voltagethrough the on-resistance of the multiplexer (about600Ω) and the comparator’s analog switches (2kΩ to5kΩ per comparator). In addition, about 12pF of straycapacitance must be charged. The input can be mod-eled as an equivalent RC network shown in Figure 9b.As RS (source impedance) increases, the capacitorstake longer to charge.
Since the length of the input acquisition time is internal-ly set, large source resistances (greater than 100Ω) willcause settling errors. The output impedance of an op-amp is its open-loop output impedance divided by theloop gain at the frequency of interest. It is importantthat the amplifier driving the converter input have suffi-cient loop gain at approximately 1MHz to maintain lowoutput impedance.
Input FilteringThe transients in the analog input caused by the sam-pled data comparators do not degrade the converter’sperformance, since the ADC does not “look” at theinput when these transients occur. The comparator’soutputs track the input during the first 1µs of the con-version, and are then latched. Therefore, at least 1µswill be provided to charge the ADC’s input capaci-tance. It is not necessary to filter these transients withan external capacitor on the AIN terminals.
Sinusoidal InputsThe MAX154/MAX158 and MX7824/MX7828 can mea-sure input signals with slew rates as high as 157mV/µsto the rated specifications. This means that the analoginput frequency can be as high as 10kHz without theaid of an external track/hold. The maximum samplingrate is limited by the conversion time (typical tCRD =2µs) plus the time required between conversions (tp =500ns). It is calculated as:
fMAX = 1 = 1 = 400kHztCRD + tp (2.0 + 0.5) µs
MX
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24
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CMOS, High-Speed, 8-Bit ADCs with Multiplexer
_______________________________________________________________________________________ 9
MAX154 MAX158
VIN
GND
VDD
REF OUT
VREF+
AINx(+)
AINx(-)
+5V
0.1µF 47µF
0.01µFVREF-
MX7824 MX7828
MX584
VIN
GND
VDD
VREF+
AINx(+)
AINx(-)
+5V
2.5V0.1µF 47µF
VREF-
MAX154 MAX158 MX7824 MX7828
VIN
GND
VDD
VREF+
AINx(+)
AINx(-)
+5V
0.1µF 47µF
VREF-
MAX154 MAX158 MX7824 MX7828
VIN
GND
* Current path must still exist from VIN(-) to Ground
VDD
VREF+
AINx(+)
AINx(-)
+5V
2.5V
0.1µF 47µF
VREF-
*
Figure 8a. Internal Reference (MAX154/MAX158 only)
Figure 8b. External Reference +2.5V Full-Scale
Figure 8c. Power Supply as Reference
Figure 8d. Inputs Not Referenced to GND
MX
78
24
/MX
78
28 fMAX permits a maximum sampling rate of 50kHz per
channel when using the MAX158/MX7828 and 100kHzper channel when using the MAX154/MX7824. Theserates are well above the Nyquist requirement of 20kHzsampling rate for a 10kHz input bandwidth.
Bipolar Input OperationThe circuit in Figure 10a can be used for bipolar inputoperation. The input voltage is scaled by an amplifier sothat only positive voltages appear at the ADC’s inputs.An external reference should be used for the MX7824/MX7828, but is not needed with the MAX154/MAX158.The analog input range is ±4V and the output code iscomplementary offset binary. The ideal input/outputcharacteristic is shown in Figure 10b.
CMOS, High-Speed, 8-Bit ADCs with Multiplexer
10 ______________________________________________________________________________________
1pFCS 12pF
CS 2pF
1pF• • •
15 LSB COMPARATORS
TO LS LADDER
RON
1pF1pF• • •
16 MSB COMPARATORS
TO MS LADDER
RON
RMUXRS
VIN
AIN1
11111111
11111110
10000010
10000001
01111111
01111110
10000000
00000001
00000000
00000010
0V
AIN INPUT VOLTAGE (LSBs)
FS = 8V 1LSB = FS / 256
11111101
+FS 2
-FS + 1LSB 2
RS
VIN
AIN1
CS1 2pF
CS2 2pF
32pF
B MUX 600Ω
RON 350Ω
MAX154 MAX158
AIN1
ONLY CHANNEL 1 SHOWN
VREF+
REF OUT
VDD
VREF-
GND
11.5Ω3.57k
10.0k
0.01µF
0.01µF
0.1µF 47µF
16.2k
VIN
+5V
CS
RDY
INT
DB0–DB7
RD
Figure 9a. Equivalent Input Circuit
Figure 10b. Transfer Function for ±4V Input OperationFigure 9b. RC Network Model
Figure 10a. Bipolar ±4V Input Operation
MX
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24
/MX
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CMOS, High-Speed, 8-Bit ADCs with Multiplexer
______________________________________________________________________________________ 11
MAX154 MAX158 MX7824 MX7828RD
RDY
*A2 ON MAX158/MX7828 ONLY.
CS
A1 A2*A0
5V
DATA BUS
A15
A0
ZBO
MREQ
WAIT
RD
DB0–DB7D0–D7
ADDRESS DECODEEN
5k
ADDRESS BUS
MAX158 MX7828
AIN2
18
26+5V
12
23
24
25
15 14
AIN8
VREF+
AIN1 CS6
5
28
+5V
27
16
RD
A1
DB0–DB7
SPEECH INPUT
A0
DATA
VDD
AIN7
BANDPASS FILTER 1
BANDPASS FILTER 2
AMP
VREF- GND
BANDPASS FILTER 7
BANDPASS FILTER 8
A2
MAX154 MX7824
AIN2 11
24 16 10
+5V
21
22
VREF-
VREF+
AIN1
INT
4
3
2
13
A0
DB0–DB7
VDD VDD
SAMPLE PULSE
VSS
CS RD
AIN3
1 AIN4
14
GND12
A1
A0
A1
15
16
17
MX7226
4
18
3
+15V
6
5
A1
VREF
AGND
DB0–DB7
2VOUT A
1
20
19
VOUT B
VOUT C
VOUT D
A0
DGND
WR
Figure 12. Speech Analysis Using Real-Time Filtering
Figure 13. 4-Channel Fast Sample and Infinite Hold
Figure 11. Simple Mode 0 Interface
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses areimplied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
12 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600
© 1995 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
MX
78
24
/MX
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28
CMOS, High-Speed, 8-Bit ADCs with Multiplexer
___________________Chip Topography_Ordering Information (continued)
±1/224 SSOP-40°C to +85°CMX7824LEAG
±124 SSOP-40°C to +85°CMX7824KEAG
±128 CERDIP-55°C to +125°CMX7828TQ
±1/228 CERDIP-55°C to +125°CMX7828UQ
±128 CERDIP-40°C to +85°CMX7828BQ
±1/228 CERDIP-40°C to +85°CMX7828CQ
±128 SSOP-40°C to +85°CMX7828KEAI
±1/228 SSOP-40°C to +85°CMX7828LEAI
±128 PLCC0°C to +70°CMX7828KP
±1/228 PLCC0°C to +70°CMX7828LP
±128 SSOP0°C to +70°CMX7828KCAI
±1/228 SSOP0°C to +70°CMX7828LCAI
±1
±1/2
±1
±1/2
±1
±1/2
±1
28 Wide SO
28 Wide SO0°C to +70°C
0°C to +70°C
±1/2
ERROR(LSB)
MX7828KCWI
MX7828LCWI
28 Plastic DIP
28 Plastic DIP
24 CERDIP-55°C to +125°C
0°C to +70°C
0°C to +70°CMX7828KN
MX7828LN
MX7824TQ
24 CERDIP
24 CERDIP
24 CERDIP
PIN-PACKAGETEMP. RANGE
-40°C to +85°C
-40°C to +85°C
-55°C to +125°CMX7824UQ
MX7824BQ
MX7824CQ
PART
A1
DB3
AIN3 (N.C.)
AIN4 (N.C.)
AIN5 (AIN1)
AIN6 (AIN2)
AIN7 (AIN3)
AIN8 (AIN4)
A0INT
GND
0.127" (3.228mm)
0.124" (3.150mm)
VREF-VREF+ ADY
A2 (N.C.)
DB7
DB6
DB5
DB4
CS
VDD A0
DB2
DB1
AIN2 (N.C.) AIN1 (N.C.)
TP (REF OUT)
DB0
( ) ARE FOR MAX154/MX7824
ANEXO A.4 – SAA1042
DeviceOperating
Temperature Range Package
SEMICONDUCTORTECHNICAL DATA
STEPPER MOTORDRIVER
ORDERING INFORMATION
SAA1042V TJ = – 30° to +125°C Plastic DIP
V SUFFIXPLASTIC PACKAGE
CASE 648C
PIN CONNECTIONS
Order this document by SAA1042/D
(Top View)
1 L316
15
14
13
12
11
10
98
7
6
5
4
3
2
Gnd
L2
Full/HalfStep
CW/CCWClock
Set/Driver Bias
VCC
Gnd Gnd
L4L1
VD VM
16
1
1MOTOROLA ANALOG IC DEVICE DATA
The SAA1042 drives a two–phase stepper motor in the bipolar mode. The
device contains three input stages, a logic section and two output stages.The IC is contained in a 16 pin dual–in–line heat tab plastic package forimproved heatsinking capability. The center four ground pins are connectedto the copper alloy heat tab and improve thermal conduction from the die tothe circuit board.
• Drive Stages Designed for Motors: 6.0 V and 12 V: SAA1042V
• 500 mA/Coil Drive Capability
• Built–In Clamp Diodes for Overvoltage Suppression
• Wide Logic Supply Voltage Range
• Accepts Commands for CW/CCW and Half/Full Step Operation
• Inputs Compatible with Popular Logic Families: MOS, TTL, DTL
• Set Input Defined Output State
• Drive Stage Bias Adaptable to Motor Power Dissipation forOptimum Efficiency
Figure 1. Representative Block Diagram
CW/CCW
3
ASet
Full/Half Step
Clock
8
10
7
VCC
Logic
11
M
VZ
VD215
VM
Driver
1
L1
L2
Driver Bias9
RBGnd
6
16
L3
L414
Driver
Motorola, Inc. 1996 Rev 2
SAA1042
2 MOTOROLA ANALOG IC DEVICE DATA
MAXIMUM RATINGS (TA = 25°C, unless otherwise noted.)
Rating Symbol SAA1042V Unit
Clamping Voltage (Pins 1, 3, 14, 16) Vclamp 20 V
Over Voltage (VOV = Vclamp – VM) VOV 6.0 V
Supply Voltage VCC 20 V
Switching or Motor Current/Coil IM 500 mA
Input Voltage (Pins 7, 8, 10) Vin clockVin Full/Half
Vin CW/CCW
VCC V
Power Dissipation (Note 1)Thermal Resistance, Junction–to–AirThermal Resistance, Junction–to–Case
PDθJAθJC
2.08015
W°C/W
Operating Junction Temperature Range TJ –30 to +125 °C
Storage Temperature Range Tstg –65 to +150 °C
NOTE: 1. The power dissipation (PD) of the circuit is given by the supply voltage (VM and VCC) and themotor current (IM), and can be determined from Figures 3 and 5. PD = Pdrive – Plogic.
ELECTRICAL CHARACTERISTICS (TA = 25°C, unless otherwise noted.)
Characteristics Pin(s) Symbol VCC Min Typ Max Unit
Supply Current 11 ICC 5.0 V20 V
——
——
3.58.5
mA
Motor Supply Current(IPin 6 = –400 µA, Pins 1, 3, 14, 16 Open)
VM = 6.0 VVM = 12 VVM = 24 V
15 IM
5.0 V5.0 V5.0 V
———
253040
———
mA
Input Voltage, High State 7, 8, 10 VIH 5.0 V10 V15 V20 V
2.07.01014
————
————
V
Input Voltage, Low State VIL 5.0 V10 V15 V20 V
————
————
0.81.52.53.5
Input Reverse Current, High State(Vin = VCC)
7, 8, 10 IIR 5.0 V10 V15 V20 V
————
————
2.02.03.05.0
µA
Input Forward Current, Low State(Vin = Gnd)
IIF 5.0 V10 V15 V20 V
–10–25–40–50
————
————
Output Voltage, High State (VM = 12 V)Iout = –500 mAIout = –50 mA
1, 3, 14, 16 VOH 5.0 –20 V —
—VM – 2.0VM – 1.2
——
V
Output Voltage, Low StateIout = 500 mAIout = 50 mA
VOL 5.0 –20 V —
—0.70.2
——
Output Leakage Current, Pin 6 = Open(VM = VD = Vclamp max)
1, 3, 14, 16 IDR 5.0 –20 V
–100 — — µA
Clamp Diode Forward Voltage (Drop at IM = 500 mA) 2 VF — — 2.5 3.5 V
Clock Frequency 7 fc 5.0 –20 V
0 — 50 kHz
Clock Pulse Width 7 tw 5.0 –20 V
10 — — µs
Set Pulse Width 6 ts — 10 — — µs
Set Control Voltage, High StateSet Control Voltage, Low State
6 — — VM—
——
—0.5
V
SAA1042
3MOTOROLA ANALOG IC DEVICE DATA
INPUT/OUTPUT FUNCTIONS
Clock — (Pin 7) This input is active on the positive edge ofthe clock pulse and accepts Logic ‘1’ input levels dependenton the supply voltage and includes hysteresis for noiseimmunity.
CW/CCW — (Pin 10) This input determines the motor’srotational direction. When the input is held low, (OV, see theelectrical characteristics) the motor’s direction is nominallyclockwise (CW). When the input is in the high state, Logic ‘1’,the motor direction is nominally counter clockwise (CCW),depending on the motor connections.
Full /Half Step — (Pin 8) This input determines the angularrotation of the motor for each clock pulse. In the low state, themotor will make a full step for each applied clock pulse, whilein the high state, the motor will make half a step.
VD — (Pin 2) This pin is used to protect the outputs (1, 3,14,16) where large positive spikes occur due to switching themotor coils. The maximum allowable voltage on these pins isthe clamp voltage (Vclamp). Motor performance is improved ifa zener diode is connected between Pin 2 and 15, as shownin Figure 1.
The following conditions have to be considered whenselecting the zener diode:
Vclamp =VZ =
VM + 6.0 VVclamp – VM – VF
where: VF = clamp diodes forward voltage dropVF = (see Figure 4)
Vclamp: ≤ 20 V for SAA1042V ≤ 30 V forVclamp: SAA1042AV
Pins 2 and 15 can be linked, in this case VZ = 0 V.
The resistor RB adapts the drivers to the motor current.1)A pulse via the resistor RB sets the outputs (1, 3, 14, 16) toa defined state.
2)
Set/Bias Input — (Pin 6) This input has two functions:
The resistor RB can be determined from the graph ofFigure 2 according to the motor current and voltage. Smallervalues of RB will increase the power dissipation of the circuitand larger values of RB may increase the saturation voltageof the driver transistors.
When the “set” function is not used, terminal A of theresistor RB must be grounded. When the set function is used,terminal A has to be connected to an open–collector (buffer)circuit. Figure 7 shows this configuration. The buffer circuit(off–state) has to sustain the motor voltage (VM). When a
pulse is applied via the buffer and the bias resistor (RB), themotor driver transistors are turned off during the pulse andafter the pulse has ended, the outputs will be in definedstates. Figure 6 shows the Timing Diagram.
Figure 7 illustrates a typical application in which theSAA1042 drives a 12 V stepper motor with a currentconsumption of 200 mA/coil. A bias resistor (RB) of 56 kΩ ischosen according to Figure 2.
The maximum voltage permitted at the output pin isVM + 6.0 V (see Maximum Ratings table), in this applicationVM = 12 V, therefore the maximum voltage is 18 V. Theoutputs are protected by the internal diodes and an externalzener connected between Pins 2 and 15.
From Figure 4, it can be seen that the voltage drop acrossthe internal diodes is about 1.7 V at 200 mA. This results in azener voltage between Pins 2 and 15 of:
VZ = 6.0 V – 1.7 V = 4.3 V.
To allow for production tolerances and a safety margin, a3.9 V zener has been chosen for this example.
The clock is derived from the line frequency which isphase–locked by the MC14046B and the MC14024. Thevoltage on the clock input is normally low (Logic ‘0’). Themotor steps on the positive going transition of the clock pulse.
The Logic ‘0’ applied to the Full/Half input (Pin 8) operatesthe motor in Full Step mode. A Logic ‘1’ at this input will resultin Half Step mode. The logic level state on the CW/CCWinput (Pin 10), and the connection of the motor coils to theoutputs determines the rotational direction of the motor.
These two inputs should be biased to a Logic ‘0’ or ‘1’ andnot left floating. In the event of non–use, they should be tiedto ground or the logic supply line, VCC.
The output drivers can be set to a fixed operating point byuse of the Set input and a bias resistor, RB. A positive pulseto this input turns the drivers off and sets the logic state of theoutputs.
After the negative going transition of the Set pulse, anduntil the first positive going transition of the clock, the outputswill be:
L1 = L3 = high and L2 = L4 = low, (see Figure 6).
The Set input can be driven by a MC14007B or a transistorwhose collector resistor is RB. If the input is not used, thebottom of R B must be grounded.
The total power dissipation of the circuit can bedetermined from Figures 3 and 5:
PD = 0.9 W + 0.08 W = 0.98 W.The junction temperature can then be computed using
Figure 8.
SAA1042
4 MOTOROLA ANALOG IC DEVICE DATA
Figure 2. Bias Resistor R B versus Motor Current Figure 3. Drive Stage Power Dissipation
5.0
3.0
MOTOR CURRENT/COIL (mA)MOTOR CURRENT/COIL (mA)00 500
4.0
1.0
2.0
0.70.5
0.3
0.2
0.14003002001007050302020 30 40 50 60 80 100 200 300 400 500
10
20
30
50
70100
200
300
500
DR
IVE
STAG
E PO
WER
DIS
SIPA
TIO
N (W
)
RB
BIAS
RES
ISTO
R (k
)Ω
VM = 24 VVM = 12 VVM = 6.0 VVM = 24 VVM = 12 V
VM = 6.0 V
Figure 4. Clamp Diode Forward Currentversus Forward Voltage
Figure 5. Power Dissipation versusLogic Supply Voltage
VF , FORWARD VOLTAGE (V)
00
VCC , SUPPLY VOLTAGE (V)
500
05.04.03.01.010
20
2.0
400
300
200
100
252015105.0
500
300
200
100
70
30
50
P
FORW
ARD
CU
RR
ENT
(mA)
D ,
POW
ER D
ISSI
PATI
ON
(mV)
Figure 6. Timing Diagram
Don’t CareFull Step Motor Drive Mode. Full/Half Step Input = 0
High Output ImpedanceClock
Clock
Half Step Motor Drive Mode. Full/Half Step Input = 1
Set
CW/CCWL1L2L3L4
SetCW/CCWL1L2L3L4
SAA1042
5MOTOROLA ANALOG IC DEVICE DATA
Figure 7. Typical ApplicationSelectable Step Rates with the Time Base Derived from the Line Frequency
220 k
Set Input
RB56 k
Steps/Sec
3510.1 µF
50 Hz
220 V
15
14
PhaseComp
MC14046B 16
12 V
VCO
761192
82 k
8.2 µF4.7 nF
120 k
f0 = 1400 Hz
12.5
25
50
100
200
400
800
1
2 7 12
5
9
6
11
4
314
53Set MC14007
VZ = 3.9 V12 V12 V
CWCCW
FullHalf
Clock
12 V
8
7
109 6
14
16
1
321511
M
MC1
4024
SAA1
042
L
L
Figure 8. Thermal Resistance and Maximum PowerDissipation versus P.C.B. Copper Length
PD(max) for TA = 70°C
RθJA 3.0 mm
1.0
0
2.0 ozCopper
2.0
10 20 30 40 50
Graph represents symmetrical layout
Printed circuit board heatsink example
0
3.0
4.0
5.0
L, LENGTH OF COPPER (mm)
100
80
60
40
20
0
RθJ
A,
THER
MAL
RES
ISTA
NC
E
P D(m
ax) ,
MAX
IMU
M P
OW
ER D
ISSI
PATI
ON
(W)
JUN
CTI
ON
–TO
–AIR
(C
/W)
°
SAA1042
6 MOTOROLA ANALOG IC DEVICE DATA
V SUFFIXPLASTIC PACKAGE
CASE 648C–03ISSUE C
OUTLINE DIMENSIONS
DIM MIN MAX MIN MAXMILLIMETERSINCHES
A 0.740 0.840 18.80 21.34B 0.240 0.260 6.10 6.60C 0.145 0.185 3.69 4.69D 0.015 0.021 0.38 0.53E 0.050 BSC 1.27 BSCF 0.040 0.70 1.02 1.78G 0.100 BSC 2.54 BSCJ 0.008 0.015 0.20 0.38K 0.115 0.135 2.92 3.43L 0.300 BSC 7.62 BSCM 0 10 0 10 N 0.015 0.040 0.39 1.01
NOTES:1. DIMENSIONING AND TOLERANCING PER ANSI
Y14.5M, 1982.2. CONTROLLING DIMENSION: INCH.3. DIMENSION L TO CENTER OF LEADS WHEN
FORMED PARALLEL.4. DIMENSION B DOES NOT INCLUDE MOLD FLASH.5. INTERNAL LEAD CONNECTION BETWEEN 4 AND
5, 12 AND 13.
–A–
–B–
16 9
1 8
F
DG
E
N
C
NOTE 5
16 PL
SAM0.13 (0.005) T
–T–SEATINGPLANE
SBM0.13 (0.005) T
J 16 PL
M
L
Motorola reserves the right to make changes without further notice to any products herein. Motorola makes no warranty, representation or guarantee regardingthe suitability of its products for any particular purpose, nor does Motorola assume any liability arising out of the application or use of any product or circuit, andspecifically disclaims any and all liability, including without limitation consequential or incidental damages. “Typical” parameters which may be provided in Motoroladata sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals”must be validated for each customer application by customer’s technical experts. Motorola does not convey any license under its patent rights nor the rights ofothers. Motorola products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or otherapplications intended to support or sustain life, or for any other application in which the failure of the Motorola product could create a situation where personal injuryor death may occur. Should Buyer purchase or use Motorola products for any such unintended or unauthorized application, Buyer shall indemnify and hold Motorolaand its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney feesarising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges thatMotorola was negligent regarding the design or manufacture of the part. Motorola and are registered trademarks of Motorola, Inc. Motorola, Inc. is an EqualOpportunity/Affirmative Action Employer.
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SAA1042/D
◊
ANEXO A.5 – 7805
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
3-TERMINAL 1A POSITIVEVOLTAGE REGULATORS
The LM78XX series of three-terminal positive regulators are available inthe TO-220/D-PAK package and with several fixed output voltages, makingthem useful in a wide range of applications. Each type employs internalcurrent limiting, thermal shut-down and safe area protection, making itessentially indestructible. If adequate heat sinking is provided, they candeliver over 1A output current. Although designed primarily as fixed voltageregulators, these devices can be used with external components to obtainadjustable voltages and currents.
FEATURES
• Output Current up to 1A• Output Voltages of 5, 6, 8, 9, 10, 11, 12, 15, 18, 24V• Thermal Overload Protection• Short Circuit Protection• Output Transistor SOA Protection
KA78XXCT ± 4%
KA78XXAT ± 2%
KA78XXIT
TO-220
-40 ~ +125 °C
KA78XXR
KA78XXAR ± 2%
KA78XXIR ± 4%
D-PAK
-40 ~ +125 °C
0 ~ +125 °C
0 ~ +125 °C
TO-220
D-PAK
1: Input 2: GND 3: Output
BLOCK DIAGRAM
1
ORDERING INFORMATION
Device Operating Temperature
± 4%
Output Voltage Tolerance
Package
1999 Fairchild Semiconductor Corporation
Rev. B
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
ABSOLUTE MAXIMUM RATINGS (TA = +25°C, unless otherwise specified)
LM7805/I/R/RI ELECTRICAL CHARACTERISTICS(Refer to test circuit, TMIN < TJ < TMAX, IO = 500mA, VI = 10V, CI= 0.33µF, CO= 0.1µF, unless otherwise specified)
* TMIN <TJ <TMAX
LM78XXI/RI: TMIN= - 40 °C, TMAX = +125 °C LM78XX/R: TMIN= 0 °C, TMAX= +125 °C
* Load and line regulation are specified at constant junction temperature. Changes in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
Characteristic Symbol Value Unit
Input Voltage (for VO = 5V to 18V)
(for VO = 24V)
VI
VI
35
40
V
V
Thermal Resistance Junction-Cases RθJC 5 °C/W
Thermal Resistance Junction-Air RθJA 65 °C/W
Operating Temperature Range KA78XX/A/R/RA
KA78XXI/RITOPR
0 ~ +125
-40 ~ +125
°C°C
Storage Temperature Range TSTG -65 ~ +150 °C
LM7805I LM7805Min Typ Max Min Typ Max
TJ =+25 °C 4.8 5.0 5.2 4.8 5.0 5.2
Output Voltage VO 5.0mA ≤ IO ≤1.0A, PO ≤ 15WVI = 7V to 20VVI = 8V to 20V 4.75 5.0 5.25
4.75 5.0 5.25 V
VO = 7V to 25V 4.0 100 4.0 100
VI = 8V to 12V 1.6 50 1.6 50
IO = 5.0mA to1.5A 9 100 9 100
IO =250mA to 750mA 4 50 4 50
Quiescent Current IQ TJ =+25 °C 5.0 8 5.0 8 mA
IO = 5mA to 1.0A 0.03 0.5 0.03 0.5
Quiescent Current Change ∆IQ VI= 7V to 25V 0.3 1.3 mA
VI= 8V to 25V 0.3 1.3
Output Voltage Drift ∆VO/∆T IO= 5mA -0.8 -0.8 mV/ °C
Output Noise Voltage VN f = 10Hz to 100Khz, TA=+25 °C 42 42 µV/Vo
Ripple Rejection
RRf = 120HzVO = 8 to 18V
62 73 62 73 dB
Dropout Voltage VO IO = 1A, TJ =+25 °C 2 2 V
Output Resistance RO f = 1KHz 15 15 mΩ Short Circuit Current ISC VI = 35V, TA =+25 °C 230 230 mA
Peak Current IPK TJ =+25 °C 2.2 2.2 A
Characteristic Symbol Test Conditions Unit
Line Regulation ∆VO
∆VO Load Regulation
TJ=+25°C
TJ=+25°C
mV
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7806/I/R/RI ELECTRICAL CHARACTERISTICS(Refer to test circuit, TMIN <TJ <TMAX, IO=500mA, VI= 11V CI= 0.33µF, CO= 0.1µF, unless otherwise specified)
* TMIN <TJ <TMAX
LM78XXI/RI: TMIN= - 40 °C, TMAX = +125 °CLM78XX/R: TMIN= 0 °C, TMAX= +125 °C
* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
LM7806I LM7806Min Typ Max Min Typ Max
TJ =+25 °C 5.75 6.0 6.25 5.75 6.0 6.25
Output Voltage VO 5.0mA ≤ IO ≤1.0A, PD ≤ 15WVI = 8.0V to 21VVI = 9.0V to 21V 5.7 6.0 6.3
5.7 6.0 6.3V
VI = 8V to 25V 5 120 5 120
VI = 9V to 13V 1.5 60 1.5 60
IO =5mA to 1.5A 9 120 9 120
IO =250mA to750A 3 60 3 60
Quiescent Current IQ TJ =+25 °C 5.0 8 5.0 8 mA
IO = 5mA to 1A 0.5 0.5
Quiescent Current Change ∆IQ VI = 8V to 25V 1.3 mA
VI = 9V to 25V 1.3
Output Voltage Drift ∆VO/∆T IO = 5mA -0.8 -0.8 mV/ °C
Output Noise Voltage VN f = 10Hz to 100Khz, TA =+25 °C 45 45 µV/VO
RippleRejection
RRf = 120HzVI = 9V to 19V
59 75 59 75 dB
Dropout Voltage VD IO = 1A, TJ =+25 °C 2 2 V
Output Resistance RD f = 1KHz 19 19 mΩShort Circuit Current ISC VI= 35V, TA=+25°C 250 250 mA
Peak Current IPK TJ =+25 °C 2.2 2.2 A
Line Regulation
Load Regulation
∆VO
∆VO
TJ=+25 °C
TJ=+25 °C
mV
mV
Characteristic Symbol Test Conditions Unit
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7808/I/R/RI ELECTRICAL CHARACTERISTICS(Refer to test Circuit, TMIN <TJ< TMAX, IO = 500mA, VI = 14V, CI = 0.33µF, CO= 0.1µF, unless otherwise specified)
* TMIN <TJ <TMAX
LM78XXI/RI: TMIN= - 40 °C, TMAX = +125 °C LM78XX/R: TMIN= 0 °C, TMAX= +125 °C* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
LM7808I LM7808Min Typ Max Min Typ Max
TJ =+25 °C 7.7 8.0 8.3 7.7 8.0 8.3
Output Voltage VO 5.0mA ≤ IO ≤ 1.0A, PO ≤ 15WVI = 10.5V to 23VVI = 11.5V to 23V 7.6 8.0 8.4
7.6 8.0 8.4V
VI = 10.5V to 25V 5.0 160 5.0 160
VI = 11.5V to 17V 2.0 80 2.0 80
IO = 5.0mA to 1.5A 10 160 10 160
IO= 250mA to 750mA 5.0 80 5.0 80
Quiescent Current IQ TJ =+25 °C 5.0 8 5.0 8 mA
IO = 5mA to 1.0A 0.05 0.5 0.05 0.5
Quiescent Current Change ∆IQ VI = 10.5A to 25V 0.5 1.0 mA
VI = 11.5V to 25V 0.5 1.0
Output Voltage Drift ∆VO/∆T IO = 5mA -0.8 -0.8 mV/ °C
Output Noise Voltage VN f = 10Hz to 100Khz, TA =+25 °C 52 52 µV/Vo
Ripple Rejection
RR f = 120Hz, VI= 11.5V to 21.5 56 73 56 73 dB
Dropout Voltage VD IO = 1A, TJ=+25 °C 2 2 V
Output Resistance RO f = 1KHz 17 17 mΩ Short Circuit Current ISC VI= 35V, TA =+25 °C 230 230 mA
Peak Current IPK TJ =+25 °C 2.2 2.2 A
Characteristic Symbol Test Conditions Unit
Line Regulation
Load Regulation
∆VO
∆VO
TJ =+ 25°C
TJ = +25°C
mV
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7809/I/R/RI ELECTRICAL CHARACTERISTICS(Refer to test circuit. TMIN < TJ <TMAX, IO= 500mA, VI= 15V, CI = 0.33µF, CO = 0.1µF. unless otherwise specified)
* TMIN <TJ <TMAX
LM78XXI/RI: TMIN= - 40 °C, TMAX = +125 °C LM78XX/R: TMIN= 0 °C, TMAX= +125 °C* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
LM7809I LM7809Min Typ Max Min Typ Max
TJ =+25 °C 8.65 9 9.35 8.65 9 9.35
Output Voltage VO 5.0mA ≤ IO ≤1.0A, PD ≤15WVI= 11.5V to 24VVI = 12.5V to 24V 8.6 9 9.4
8.6 9 9.4V
VI = 11.5V to 25V 6 180 6 180
VI = 12V to 25v 2 90 2 90
IO = 5mA to 1.5A 12 180 12 180
IO = 250mA to 750mA 4 90 4 90
Quiescent Current IQ TJ=+25 °C 5.0 8 5.0 8 mA
IO = 5mA to 1.0A 0.5 0.5
Quiescent Current Change ∆IQ VI = 11.5V to 26V 1.3 mA
VI = 12.5V to 26V 1.3
Output Voltage Drift ∆VO/∆T IO = 5mA -1 -1 mV/ °C
Output Noise Voltage VN f = 10Hz to 100Khz, TA =+25 °C 58 58 µV/VO
Ripple Rejection
RRf = 120HzVI = 13V to 23V
56 71 56 71 dB
Dropout Voltage VD IO = 1A, TJ=+25 °C 2 2 V
Output Resistance RO f = 1KHz 17 17 mΩ Short Circuit Current ISC VI= 35V, TA =+25 °C 250 250 mA
Peak Current IPK TJ= +25 °C 2.2 2.2 A
Characteristic Symbol Test Conditions
Line Regulation
Load Regulation
∆VO
∆VO
TJ=+25 °C
TJ=+25 °C
mV
mV
Unit
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7810/I/R/RI ELECTRICAL CHARACTERISTICS (Refer to test circuit, TMIN <TJ <TMAX, IO= 500mA, VI =16V, CI = 0.33µF, CO= 0.1µF, unless otherwise specified)
* TMIN <TJ <TMAX
LM78XXI/RI: TMIN= - 40 °C, TMAX = +125 °C LM78XX/R: TMIN= 0 °C, TMAX= +125 °C* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
LM7810I LM7810Min Typ Max Min Typ Max
TJ =+25 °C 9.6 10 10.4 9.6 10 10.4
Output Voltage VO 5.0mA ≤ IO≤1.0A, PD ≤15WVI = 12.5V to 25VVI= 13.5V to 25V 9.5 10 10.5
9.5 10 10.5V
VI = 12.5V to 25V 10 200 10 200
VI = 13V to 25V 3 100 3 100
IO = 5mA to 1.5A 12 200 12 200
IO = 250mA to 750mA 4 400 4 400
Quiescent Current IQ TJ =+25 °C 5.1 8 5.1 8 mA
IO = 5mA to 1.0A 0.5 0.5
Quiescent Current Change ∆IQ VI = 12.5V to 29V 1.0 mA
VI = 13.5V to 29V 1.0
Output Voltage Drift ∆VO/∆T IO = 5mA -1 -1 mV/ °C
Output Noise Voltage VN f = 10Hz to 100Khz, TA =+25 °C 58 58 µV/Vo
Ripple Rejection
RRf = 120HzVI = 13V to 23V
56 71 56 71 dB
Dropout Voltage VD IO = 1A, TJ=+25 °C 2 2 V
Output Resistance RO f = 1KHz 17 17 mΩ Short Circuit Current ISC VI = 35V, TA=+25 °C 250 250 mA
Peak Current IPK TJ =+25 °C 2.2 2.2 A
Unit
Line Regulation ∆VO
∆VO
TJ =+25°C
TJ =+25°C Load Regulation
Characteristic Symbol Test Conditions
mV
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7811/I/R/RI ELECTRICAL CHARACTERISTICS(Refer to test circuit, TMIN<TJ<TMAX, IO = 500mA, VI=18V, CI=0.33µF, CO = 0.IµF, unless otherwise specified)
* TMIN <TJ <TMAX
LM78XXI/RI: TMIN= - 40 °C, TMAX = +125 °C LM78XX/R: TMIN= 0 °C, TMAX= +125 °C* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
LM7811I LM7811Min Typ Max Min Typ Max
TJ =+25 °C 10.6 11 11.4 10.6 11 11.4
Output Voltage VO 5.0mA ≤ IO ≤1.0A, PD ≤15WVI = 13.5V to 26VVI= 14.5V to 26V 10.5 11 11.5
10.5 11 11.5V
VI = 13.5V to 25V 10 220 10 220
VI = 14V to 21V 3.0 110 3 110
IO = 5.0mA to 1.5A 12 220 12 220
IO = 250mA to 750mA 4 110 4 110
Quiescent Current IQ TJ =+25 °C 5.1 8 5.1 8 mA
IO = 5mA to 1.0A 0.5 0.5
Quiescent Current Change ∆IQ VI = 13.5V to 29V 1.0 mA
VI = 14.5V to 29V 1.0
Output Voltage Drift ∆VO/∆T IO = 5mA -1 -1 mV/ °C
Output Noise Voltage VN f = 10Hz to 100Khz, TA =+25 °C 70 70 µV/VO
Ripple Rejection
RRf = 120HzVI = 14V to 24V
55 71 55 71 dB
Dropout Voltage VD IO = 1A, TJ=+25 °C 2 2 V
Output Resistance RO f = 1KHz 18 18 mΩ Short Circuit Current ISC VI = 35V, TA=+25 °C 250 250 mA
Peak Current IPK TJ =+25 °C 2.2 2.2 A
Unit
Line Regulation ∆VO
∆VO
TJ =+25°C
TJ =+25°C Load Regulation
Characteristic Symbol Test Conditions
mV
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7812/I/R/RI ELECTRICAL CHARACTERISTICS (Refer to test circuit, TMIN <TJ <TMAX, IO=500mA, VI=19V, CI= 0.33µF, CO= 0.1.µF, unless otherwise specified)
TMIN <TJ <TMAX
LM78XXI/RI: TMIN= - 40 °C, TMAX = +125 °C LM78XX/R: TMIN= 0 °C, TMAX= +125 °C* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
LM7812I LM7812Min Typ Max Min Typ Max
TJ =+25 °C 11.5 12 12.5 11.5 12 12.5
Output Voltage VO 5.0mA ≤ IO≤1.0A, PD≤15WVI = 14.5V to 27VVI= 15.5V to 27V 11.4 12 12.6
11.4 12 12.6V
VI = 14.5V to 30V 10 240 10 240
VI = 16V to 22V 3.0 120 3.0 120
IO = 5mA to 1.5A 11 240 11 240
IO = 250mA to 750mA 5.0 120 5.0 120
Quiescent Current IQ TJ =+25 °C 5.1 8 5.1 8 mA
IO = 5mA to 1.0A 0.1 0.5 0.1 0.5
Quiescent Current Change ∆IQ VI = 14.5V to 30V 0.5 1.0 mA
VI = 15V to 30V 1.0
Output Voltage Drift ∆VO/∆T IO = 5mA 0.5 -1 -1 mV/ °C
Output Noise Voltage VN f = 10Hz to 100Khz, TA =+25 °C 76 76 mV/VO
Ripple Rejection
RRf = 120HzVI = 15V to 25V
55 71 55 71 dB
Dropout Voltage VD IO = 1A, TJ=+25 °C 2 2 V
Output Resistance RO f = 1KHz 18 18 mΩ Short Circuit Current ISC VI = 35V, TA=+25 °C 230 230 mA
Peak Current IPK TJ = +25 °C 2.2 2.2 A
Unit
Line Regulation ∆VO
∆VO
TJ =+25°C
TJ =+25°C Load Regulation
Characteristic Symbol Test Conditions
mV
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7815/I/R/RI ELECTRICAL CHARACTERISTICS (Refer to test circuit, TMIN<TJ<TMAX, IO =500mA, VI =23V, CI =0.33µF, CO =0.1µF, unless otherwise specified)
* TMIN <TJ <TMAX
LM78XXI/RI: TMIN= - 40 °C, TMAX = +125 °C LM78XX/R: TMIN= 0 °C, TMAX= +125 °C* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
LM7815I LM7815Min Typ Max Min Typ Max
TJ =+25 °C 14.4 15 15.6 14.4 15 15.6
Output Voltage VO 5.0mA ≤ IO≤1.0A, PD≤15WVI = 17.5V to 30VVI= 18.5V to 30V
14.25
15 15.75 14.25 15 15.75V
VI = 17.5V to 30V 11 300 11 300
VI = 20V to 26V 3 150 3 150
IO = 5mA to 1.5A 12 300 12 300
IO = 250mA to 750mA 4 150 4 150
Quiescent Current IQ TJ =+25 °C 5.2 8 5.2 8 mA
IO = 5mA to 1.0A 0.5 0.5
Quiescent Current Change ∆IQ VI = 17.5V to 30V 1.0 mA
VI = 18.5V to 30V 1.0
Output Voltage Drift ∆VO/∆T IO = 5mA -1 -1 mV/ °C
Output Noise Voltage VN f = 10Hz to 100Khz, TA =+25 °C 90 90 µV/VO
Ripple Rejection
RRf = 120HzVI = 18.5V to 28.5V
54 70 54 70 dB
Dropout Voltage VD IO = 1A, TJ=+25 °C 2 2 V
Output Resistance RO f = 1KHz 19 19 mΩ Short Circuit Current ISC VI = 35V, TA=+25 °C 250 250 mA
Peak Current IPK TJ =+25 °C 2.2 2.2 A
Unit
Line Regulation ∆VO
∆VO
TJ =+25°C
TJ =+25°C Load Regulation
Characteristic Symbol Test Conditions
mV
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7818/I/R/RI ELECTRICAL CHARACTERISTICS(Refer to test circuit, TMIN<TJ<TMAX, IO =500mA, VI =27V, CI =0.33µF, CO =0.1µF, unless otherwise specified)
* TMIN <TJ <TMAX
LM78XXI/RI: TMIN= - 40 °C, TMAX = +125 °C LM78XX/R: TMIN= 0 °C, TMAX= +125 °C* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
LM7818I LM7818Min Typ Max Min Typ Max
TJ =+25 °C 17.3 18 18.7 17.3 18 18.7
Output Voltage VO 5.0mA ≤ IO ≤1.0A, PD ≤15WVI = 21V to 33VVI= 22V to 33V 17.1 18 18.9
17.1 18 18.9V
VI = 21V to 33V 15 360 15 360
VI = 24V to 30V 5 180 5 180
IO = 5mA to 1.5A 15 360 15 360
IO = 250mA to 750mA 5.0 180 5.0 180
Quiescent Current IQ TJ =+25 °C 5.2 8 5.2 8 mA
IO = 5mA to 1.0A 0.5 0.5
Quiescent Current Change ∆IQ VI = 21V to 33V 1 mA
VI = 22V to 33V 1.0
Output Voltage Drift ∆VO/∆T IO = 5mA -1 -1 mV/ °C
Output Noise Voltage VN f = 10Hz to 100Khz, TA =+25 °C 110 110 µV/VO
Ripple Rejection
RRf = 120HzVI = 22V to 32V
53 69 53 69 dB
Dropout Voltage VD IO = 1A, TJ=+25 °C 2 2 V
Output Resistance RO f = 1KHz 22 22 mΩ Short Circuit Current ISC VI = 35V, TA=+25 °C 250 250 mA
Peak Current IPK TJ =+25 °C 2.2 2.2 A
Unit
Line Regulation ∆VO
∆VO
TJ =+25°C
TJ =+25°C Load Regulation
Characteristic Symbol Test Conditions
mV
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7824/I/R/RI ELECTRICAL CHARACTERISTICS(Refer to test circuit, TMIN<TJ<TMAX, IO = 500mA, VI = 33V, CI = 0.33µF, CO = 0.1µF, unless otherwise specified)
* TMIN <TJ <TMAX
LM78XXI/RI: TMIN= - 40 °C, TMAX = +125 °C LM78XX/R: TMIN= 0 °C, TMAX= +125 °C* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
LM7824I LM7824Min Typ Max Min Typ Max
TJ =+25 °C 23 24 25 23 24 25
Output Voltage VO 5.0mA ≤ IO ≤ 1.0A, PD ≤ 15WVI = 27V to 38VVI= 28V to 38V 22.8 24 25.2
22.8 24 25.25V
VI = 27V to 38V 17 480 17 480
VI = 30V to 36V 6 240 6 240
IO = 5mA to 1.5A 15 480 15 480
IO = 250mA to 750mA 5.0 240 5.0 240
Quiescent Current IQ TJ =+25 °C 5.2 8 5.2 8 mA
IO = 5mA to 1.0A 0.1 0.5 0.1 0.5
Quiescent Current Change ∆IQ VI = 27V to 38V 0.5 1 mA
VI = 28V to 38V 0.5 1
Output Voltage Drift ∆VO/∆T IO = 5mA -1.5 -1.5 mV/ °C
Output Noise Voltage VN f = 10Hz to 100KHz, TA =+25 °C 160 60 µV/VO
Ripple Rejection
RRf = 120HzVI = 28V to 38V
50 67 50 67 dB
Dropout Voltage VD IO = 1A, TJ=+25 °C 2 2 V
Output Resistance RO f = 1KHz 28 28 mΩ Short Circuit Current ISC VI = 35V, TA=+25 °C 230 230 mA
Peak Current IPK TJ =+25 °C 2.2 2.2 A
Unit
Line Regulation ∆VO
∆VO
TJ =+25°C
TJ =+25°C Load Regulation
Characteristic Symbol Test Conditions
mV
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7805A/RA ELECTRICAL CHARACTERISTICS(Refer to the test circuits. TJ = 0 to +I25 °C, IO = 1A, V I = 10V, C I= 0.33µF, C O= 0.1µF, unless otherwise specified)
*Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
Characteristic Symbol Test Conditions Min Typ Max Unit
TJ =+25 °C 4.9 5 5.1
Output Voltage VO IO = 5mA to 1A, PD ≤ 5W VI = 7.5 to 20V
4.8 5 5.2V
VI = 7.5 to 25V IO = 500mA
5 50
Line Regulation ∆VO VI = 8V to 12V 3 50 V
VI= 7.3V to 25V 5 50
VI= 8V to 12V 1.5 25
TJ =+25 °C IO = 5mA to 1.5A
9 100
IO = 5mA to 1A 9 100
IO = 250 to 750mA 4 50
Quiescent Current IQ TJ =+25 °C 5.0 6 mA
IO = 5mA to 1A 0.5
Quiescent Current Change ∆IQ VI = 8 V to 25V, IO = 500mA 0.8 mA
VI = 7.5V to 20V, TJ =+25 °C 0.8
Output Voltage Drift -0.8 mV/ °C
Output Noise Voltage VN f = 10Hz to 100KHz TA =+25 °C
10
Ripple RejectionRR f = 120Hz, IO = 500mA
VI = 8V to 18V68 dB
Dropout Voltage VD IO = 1A, TJ =+25 °C 2 V
Output Resistance RO f = 1KHz 17 mΩ Short Circuit Current ISC VI= 35V, TA =+25 °C 250 mA
Peak Current IPK TJ= +25 °C 2.2 A
Load Regulation ∆VO
TJ =+25 °C
∆V/∆T IO = 5mA
µV/VO
V
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7806A/RA ELECTRICAL CHARACTERISTICS (Refer to the test circuits. TJ = 0 to+150 °C, IO = 1A, V I = 11V, C I= 0.33µF, C O= 0.1µF, unless otherwise specified)
* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
Characteristic Symbol Test Conditions Min Typ Max Unit
TJ =+25 °C 5.58 6 6.12
Output Voltage VO IO = 5mA to 1A, PD ≤ 15W VI = 8.6 to 21V
5.76 6 6.24V
VI= 8.6 to 25V IO = 500mA
5 60
Line Regulation ∆VO VI= 9V to 13V 3 60 mV
VI= 8.3V to 21V 5 60
VI= 9V to 13V 1.5 30
TJ =+25 °C IO = 5mA to 1.5A
9 100
IO = 5mA to 1A 4 100
IO = 250 to 750mA 5.0 50
Quiescent Current IQ TJ =+25 °C 4.3 6 mA
IO = 5mA to 1A 0.5
Quiescent Current Change ∆IQ VI = 9V to 25V, IO = 500mA 0.8 mA
VI= 8.5V to 21V, TJ =+25 °C 0.8
Output Voltage Drift IO = 5mA
-0.8 mV/ °C
Output Noise Voltage VN f = 10Hz to 100KHz TA =+25 °C
10 µ V/VO
Ripple Rejection RR f = 120Hz, IO = 500mA VI = 9V to 19V
65 dB
Dropout Voltage VD IO = 1A, TJ =+25 °C 2 V
Output Resistance RO f = 1KHz 17 mΩ Short Circuit Current ISC VI= 35V, TA =+25 °C 250 mA
Peak Current IPK TJ=+25 °C 2.2 A
Load Regulation ∆VO
TJ =+25 °C
∆V/∆T
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7808A/RA ELECTRICAL CHARACTERISTICS (Refer to the test circuits. TJ = 0 to+150 °C, IO = 1A, V I = 14V, C I = 0.33µF, C O=0.1µF, unless otherwise specified)
* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
Characteristic Symbol Test Conditions Min Typ Max Unit
TJ =+25 °C 7.84 8 8.16
Output Voltage VO IO = 5mA to 1A, PD ≤15W VI = 8.6 to 21V
7.7 8 8.3V
VI= 10.6 to 25V IO = 500mA
6 80
Line Regulation ∆VO VI= 11to 17V 3 80 mV
VI= 10.4V to 23V 6 80
VI= 11V to 17V 2 40
TJ =+25 °C IO = 5mA to 1.5A
12 100
IO = 5mA to 1A 12 100
IO = 250 to 750mA 5 50
Quiescent Current IQ TJ =+25 °C 5.0 6 mA
IO = 5mA to 1A 0.5
Quiescent Current Change ∆IQ VI = 11V to 25V, IO = 500mA 0.8 mA
VI= 10.6V to 23V, TJ =+25 °C 0.8
Output Voltage Drift IO = 5mA -0.8 mV /°C
Output Noise Voltage VN f = 10Hz to 100KHz TA =+25 °C
10 µV/VO
Ripple Rejection RR f = 120Hz, IO = 500mA VI = 11.5V to 21.5V
62 dB
Dropout Voltage VD IO = 1A, TJ =+25 °C 2 V
Output Resistance RO f = 1KHz 18 mΩ Short Circuit Current ISC VI= 35V, TA =+25°C 250 mA
Peak Current IPK TJ=+25 °C 2.2 A
Load Regulation ∆VO
TJ =+25 °C
∆V/∆T
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7809A/RA ELECTRICAL CHARACTERISTICS(Refer to the test circuits. TJ = 0 to +125 °C, IO = 1A, V I = 15V, C I = 0.33µF, C O = 0.1µF, unless otherwise specified)
* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
Characteristic Symbol Test Conditions Min Typ Max Unit
TJ =+25 °C 8.82 9.0 9.18
Output Voltage VO IO = 5mA to 1A, PD ≤15W VI = 11.2 to 24V
8.65 9.0 9.35V
VI= 11.7 to 25V IO = 500mA
6 90
Line Regulation ∆VO VI= 12.5 to 19V 4 45 mV
VI= 11.5V to 24V 6 90
VI= 12.5V to 19V 2 45
TJ =+25 °C IO = 5mA to 1.0A
12 100
IO = 5mA to 1.0A 12 100
IO = 250 to 750mA 5 50
Quiescent Current IQ TJ =+25 °C 5.0 6.0 mA
VI = 11.7V to 25V, TJ=+25 °C 0.8
Quiescent Current Change ∆IQ VI = 12V to 25V, IO = 500mA 0.8 mA
IO = 5mA to 1.0A 0.5
Output Voltage Drift IO = 5mA -1.0 mV/ °C
Output Noise Voltage VN f = 10Hz to 100KHz TA =+25 °C
10
Ripple Rejection RR f = 120Hz, IO = 500mA VI = 12V to 22V
62 dB
Dropout Voltage VD IO = 1A, TJ =+25 °C 2.0 V
Output Resistance RO f = 1KHz 17 mΩ Short Circuit Current ISC VI= 35V, TA =+25 °C 250 mA
Peak Current IPK TJ=+25 °C 2.2 A
Load Regulation ∆VO
TJ =+25 °C
∆V/∆T
µV/VO
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7810A/RA ELECTRICAL CHARACTERISTICS (Refer to the test circuits. TJ = 0 to+125 °C, IO = 1A, V I = 16V, C I = 0.33µF, CO = 0.1µF, unless otherwise specified)
* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
Characteristic Symbol Test Conditions Min Typ Max Unit
TJ =+25 °C 9.8 10 10.2
Output Voltage VO IO = 5mA to 1A, PD ≤ 15W VI =12.8 to 25V
9.6 10 10.4V
VI= 12.8 to 26V IO = 500mA
8 100
Line Regulation ∆VO VI= 13to 20V 4 50 mV
VI= 12.5V to 25V 8 100
VI= 13V to 20V 3 50
TJ =+25 °C IO = 5mA to 1.5A
12 100
IO = 5mA to 1.0A 12 100
IO = 250 to 750mA 5 50
Quiescent Current IQ TJ =+25 °C 5.0 6.0 mA
VI = 13V to 26V, TJ=+25 °C 0.5
Quiescent Current Change ∆IQ VI = 12.8V to 25V, IO = 500mA 0.8 mA
IO = 5mA to 1.0A 0.5
Output Voltage Drift IO = 5mA -1.0mV °C
Output Noise Voltage VN f = 10Hz to 100KHz TA =+25 °C
10
Ripple Rejection RR f = 120Hz, IO = 500mA VI = 14V to 24V
62 dB
Dropout Voltage VD IO = 1A, TJ =+25 °C 2.0 V
Output Resistance RO f = 1KHz 17 mΩ Short Circuit Current ISC VI= 35V, TA =+25 °C 250 mA
Peak Current IPK TJ=+25 °C 2.2 A
Load Regulation ∆VO
TJ =+25 °C
∆V/∆T
µV/VO
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7811A/RA ELECTRICAL CHARACTERISTICS(Refer to the test circuits. TJ = 0 to +125 °C, IO = 1A, V I = 18V, C I = 0.33µF, C O = 0.1µF, unless otherwise specified)
* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
Characteristic Symbol Test Conditions Min Typ Max Unit
TJ =+25 °C 10.8 11.0 11.2
Output Voltage VO IO = 5mA to 1A, PD ≤15W VI = 13.8 to 26V
10.6 11.0 11.4V
VI= 12.8 to 26V IO = 500mA
10 110
Line Regulation ∆VO VI= 15 to 21V 4 55 mV
VI= 13.5V to 26V 10 110
VI= 15V to 21V 3 55
TJ =+25 °C IO = 5mA to 1.5A
12 100
IO = 5mA to 1.0A 12 100
IO = 250 to 750mA 5 50
Quiescent Current IQ TJ =+25 °C 5.1 6.0 mA
VI = 13.8V to 26V, TJ=+25 °C 0.8
Quiescent Current Change ∆IQ VI = 14V to 27V, IO = 500mA 0.8 mA
IO = 5mA to 1.0A 0.5
Output Voltage Drift ∆VO/∆T IO = 5mA -1.0 mV /°C
Output Noise Voltage VN f = 10Hz to 100KHz TA =+25 °C
10
Ripple Rejection RR f = 120Hz, IO = 500mA VI = 14V to 24V
61 dB
Dropout Voltage VD IO = 1A, TJ =+25 °C 2.0 V
Output Resistance RO f = 1KHz 18 mΩ Short Circuit Current ISC VI= 35V, TA =+25 °C 250 mA
Peak Current IPK TJ=+25 °C 2.2 A
Load Regulation ∆VO
TJ =+25 °C
µV/VO
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7812A/RA ELECTRICAL CHARACTERISTICS(Refer to the test circuits. TJ = 0 to +125 °C, IO = 1A, V I = 19V, C I = 0.33µF, C O= 0.1µF, unless otherwise specified)
* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
Characteristic Symbol Test Conditions Min Typ Max Unit
TJ =+25 °C 11.75 12 12.25
Output Voltage VO IO = 5mA to 1A, PD ≤15W VI = 14.8 to 27V
11.5 12 12.5V
VI= 14.8 to 30V IO = 500mA
10 120
Line Regulation ∆VO VI= 16 to 22V 4 120 mV
VI= 14.5V to 27V 10 120
VI= 16V to 22V 3 60
TJ =+25°C IO = 5mA to 1.5A
12 100
IO = 5mA to 1.0A 12 100
IO = 250 to 750mA 5 50
Quiescent Current IQ TJ =+25 °C 5.1 6.0 mA
VI = 15V to 30V, TJ=+25 °C 0.5
Quiescent Current Change ∆IQ VI = 14V to 27V, IO = 500mA 0.8 mA
IO = 5mA to 1.0A 0.8
Output Voltage Drift ∆VO/∆T IO = 5mA -1.0 mV/ °C
Output Noise Voltage VN f = 10Hz to 100KHz TA =+25 °C
10
Ripple Rejection RR f = 120Hz, IO = 500mA VI = 14V to 24V
60 dB
Dropout Voltage VD IO = 1A, TJ =+25 °C 2.0 V
Output Resistance RO f = 1KHz 18 mΩ Short Circuit Current ISC VI= 35V, TA =+25 °C 250 mA
Peak Current IPK TJ=+25 °C 2.2 A
Load Regulation ∆VO mV
µV/VO
TJ =+25°C
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7815A/RA ELECTRICAL CHARACTERISTICS(Refer to the test circuits. TJ = 0 to +150 °C, IO =1A, V I=23V, C I = 0.33µF, C O=0.1µF, unless otherwise specified)
* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
Characteristic Symbol Test Conditions Min Typ Max Unit
TJ =+25 °C 14.7 15 15.3
Output Voltage VO IO = 5mA to 1A, PD ≤15W VI = 17.7 to 30V
14.4 15 15.6V
VI= 17.9 to 30V IO = 500mA
10 150
Line Regulation ∆VO VI= 20 to 26V 5 150 mV
VI= 17.5V to 30V 11 150
VI= 20V to 26V 3 75
TJ =+25 °C IO = 5mA to 1.5A
12 100
IO = 5mA to 1.0A 12 100
IO = 250 to 750mA 5 50
Quiescent Current IQ TJ =+25 °C 5.2 6.0 mA
VI = 17.5V to 30V, TJ =+25 °C 0.5
Quiescent Current Change ∆IQ VI = 17.5V to 30V, IO = 500mA 0.8 mA
IO = 5mA to 1.0A 0.8
Output Voltage Drift ∆VO/∆T IO = 5mA -1.0 mV/ °C
Output Noise Voltage VN f = 10Hz to 100KHz TA =+25 °C
10
Ripple Rejection RR f = 120Hz, IO = 500mA VI = 18.5V to 28.5V
58 dB
Dropout Voltage VD IO = 1A, TJ =+25 °C 2.0 V
Output Resistance RO f = 1KHz 19 mΩ Short Circuit Current ISC VI= 35V, TA =+25 °C 250 mA
Peak Current IPK TJ=+25 °C 2.2 A
Load Regulation ∆VO
TJ =+25 °C
µV/VO
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7818A/RA ELECTRICAL CHARACTERISTICS (Refer to the test circuits. TJ = 0 to +150 °C, IO=1A, V I = 27V, C I= 0.33µF, C O = 0.1µF, unless otherwise specified)
* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
Characteristic Symbol Test Conditions Min Typ Max Unit
TJ =+25 °C 17.64 18 18.36
Output Voltage VO IO = 5mA to 1A, PD ≤15W VI = 21 to 33V
17.3 18 18.7V
VI= 21 to 33V IO = 500mA
15 180
Line Regulation ∆VO VI= 21 to 33V 5 180 mV
VI= 20.6V to 33V 15 180
VI= 24V to 30V 5 90
TJ =+25 °C IO = 5mA to 1.5A
15 100
IO = 5mA to 1.0A 15 100
IO = 250 to 750mA 7 50
Quiescent Current IQ TJ =+25 °C 5.2 6.0 mA
VI = 21V to 33V, TJ=+25 °C 0.5
Quiescent Current Change ∆IQ VI = 21V to 33V, IO = 500mA 0.8 mA
IO = 5mA to 1.0A 0.8
Output Voltage Drift ∆VO/∆T IO = 5mA -1.0 mV/ °C
Output Noise Voltage VN f = 10Hz to 100KHz TA =+25 °C
10
Ripple Rejection RR f = 120Hz, IO = 500mA VI = 18.5V to 28.5V
57 dB
Dropout Voltage VD IO = 1A, TJ =+25 °C 2.0 V
Output Resistance RO f = 1KHz 19 mΩ Short Circuit Current ISC VI= 35V, TA =+25 °C 250 mA
Peak Current IPK TJ=+25 °C 2.2 A
Load Regulation ∆VO
TJ =+25 °C
µV/VO
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
LM7824A/RA ELECTRICAL CHARACTERISTICS(Refer to the test circuits. TJ = 0 to +150 °C, IO =1A, V I = 33V, C I= 0.33µF, C O=0.1µF, unless otherwise specified)
* Load and line regulation are specified at constant, junction temperature. Change in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used.
Characteristic Symbol Test Conditions Min Typ Max Unit
TJ =+25 °C 23.5 24 24.5
Output Voltage VO IO = 5mA to 1A, PD ≤15W VI = 27.3 to 38V
23 24 25V
VI= 27 to 38V IO = 500mA
18 240
Line Regulation ∆VO VI= 21 to 33V 6 240 mV
VI= 26.7V to 38V 18 240
VI= 30V to 36V 6 120
TJ =+25 °C IO = 5mA to 1.5A
15 100
IO = 5mA to 1.0A 15 100
IO = 250 to 750mA 7 50
Quiescent Current IQ TJ =+25 °C 5.2 6.0 mA
VI = 27.3V to 38V, TJ =+25 °C 0.5
Quiescent Current Change ∆IQ VI = 27.3V to 38V, IO = 500mA 0.8 mA
IO = 5mA to 1.0A 0.8
Output Voltage Drift ∆VO/∆T IO = 5mA -1.5 mV/ °C
Output Noise Voltage VN f = 10Hz to 100KHz TA = 25 °C
10
Ripple Rejection RR f = 120Hz, IO = 500mA VI = 18.5V to 28.5V
54 dB
Dropout Voltage VD IO = 1A, TJ =+25°C 2.0 V
Output Resistance RO f = 1KHz 20 mΩ Short Circuit Current ISC VI= 35V, TA =+25 °C 250 mA
Peak Current IPK TJ=+25 °C 2.2 A
Load Regulation ∆VO
TJ =+25 oC
µV/VO
mV
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
TYPICAL PERFORMANCE CHARACTERISTICS
Fig. 1 Quiescent Current Fig. 2 Peak Output Current
Fig. 3 Output Voltage Fig. 4 Quiescent Current
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
TYPICAL APPLICATIONS
Fig. 5 DC Parameters
Fig. 6 Load Regulation
Fig. 7 Ripple Rejection
TYPICAL APPLICATIONS (Continued)
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
Fig. 8 Fixed Output Regulator Fig. 9 Constant Current Regulator
Notes:(1) To specify an output voltage. substitute voltage value for "XX."
A common ground is required between the input and the Output voltage. The input voltage must remain typically 2.0V above the output voltage even during the low point on the input ripple voltage.
(2) CI is required if regulator is located an appreciable distance from power Supply filter.(3) CO improves stability and transient response.
Fig. 10 Circuit for Increasing Output Voltage Fig. 11 Adjustable Output Regulator (7 to 30V)
IRI ≥ 5 IQ VO = VXX (1+R2/R1)+IQR2
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
TYPICAL APPLICATIONS (Continued)
Fig. 12 High Current Voltage Regulator Fig. 13 High Output Current with Short Circuit Protection
Fig. 14 Tracking Voltage Regulator Fig. 15 Split Power Supply ( ±±15V-1A)
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
TYPICAL APPLICATIONS (Continued)
Fig. 16 Negative Output Voltage Circuit Fig. 17 switching Regulator
LM78XX (KA78XX, MC78XX) FIXED VOLTAGE REGULATOR (POSITIVE)
TRADEMARKS
ACEx™CoolFET™CROSSVOLT™E2CMOSTM
FACT™FACT Quiet Series™FAST®
FASTr™GTO™HiSeC™
The following are registered and unregistered trademarks Fairchild Semiconductor owns or is authorized to use and isnot intended to be an exhaustive list of all such trademarks.
LIFE SUPPORT POLICY
FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORTDEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF FAIRCHILD SEMICONDUCTOR CORPORATION.As used herein:
ISOPLANAR™MICROWIRE™POP™PowerTrench™QS™Quiet Series™SuperSOT™-3SuperSOT™-6SuperSOT™-8TinyLogic™
1. Life support devices or systems are devices orsystems which, (a) are intended for surgical implant intothe body, or (b) support or sustain life, or (c) whosefailure to perform when properly used in accordancewith instructions for use provided in the labeling, can bereasonably expected to result in significant injury to theuser.
2. A critical component is any component of a lifesupport device or system whose failure to perform canbe reasonably expected to cause the failure of the lifesupport device or system, or to affect its safety oreffectiveness.
PRODUCT STATUS DEFINITIONS
Definition of Terms
Datasheet Identification Product Status Definition
Advance Information
Preliminary
No Identification Needed
Obsolete
This datasheet contains the design specifications forproduct development. Specifications may change inany manner without notice.
This datasheet contains preliminary data, andsupplementary data will be published at a later date.Fairchild Semiconductor reserves the right to makechanges at any time without notice in order to improvedesign.
This datasheet contains final specifications. FairchildSemiconductor reserves the right to make changes atany time without notice in order to improve design.
This datasheet contains specifications on a productthat has been discontinued by Fairchild semiconductor.The datasheet is printed for reference information only.
Formative orIn Design
First Production
Full Production
Not In Production
DISCLAIMER
FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHERNOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILDDOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCTOR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENTRIGHTS, NOR THE RIGHTS OF OTHERS.
ANEXO B – Esquemático
ANEXO B.1 – Drivers
1
1
2
2
3
3
4
4
A A
B B
D04AZ3_3
D1
bd243
Q7
bd243
Q6
bd243
Q8
1k
R1
R4
150
R5
150
R6
150
R7
150
bd243
Q5
1 2 3
U9
BORN-3
1 2 3
U10
BORN-3
1 2 3
U11
BORN-3
1 L22 VD3L1
6SET7CLK8F/H
16L315VM14L4
11VCC10
CW/CCW 9GND
saa1042U4
VINGND
+5V
7805U15
VINGND
+5V
7805U14
-Revision:
Page Size:
Pedro Silva
BEscola Superior de Tecnologia
Pagina de
Setubal
Luis Rita
6 de Outubro de 2003 11
GN
D+5
VV D
ir_x
Freq
_xL4 L3 L1L2
ANEXO B.2 – Principal
1
1
2
2
3
3
4
4
A A
B B
11M
C2
2 4
U38
botaoR9
470
47uC6
100nC7
33pC5
33pC4
1u
C3
10k
R1 R2
10k
R3
10k
R4
10k
R6
10k
R7
10k
R8
10k
R5
10k
220 R10
220 R11
220 R13
220 R12
D18
ledD19
led
led
D17
D16
led
12
U34
ldr
12ldr
U33 12ldr
U32 12ldr
U31 12ldr
U30 12ldr
U29 12ldr
U28 12ldr
U27
VINGND
+5VU21 7805
AIN6AIN5AIN4AIN3AIN2AIN1TPDB0BD1DB2DB3/RD/INTGND
AIN7AIN8VDD
A0A1A2
DB7DB6DB5DB4/CS
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MX7828U17
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U13T2INT1INR1OUTR1INT1OUTGNDVCCC1+GNDCS-
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MAX233U2
FONTE
SERIE1 SERIE2
Freq_1D
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Dir_2
Freq_2
-Revision:
Page Size: BEscola Superior de TecnologiaSetubal
Luis RitaPedro Silva
Pagina de6 de Outubro de 2003 11
ANEXO C – PCB
ANEXO C.1 – Drivers
ANEXO C.2 – Principal
ANEXO C.3 – Pistas para os contactos deslizantes
ANEXO D – Programa do Microcontrolador
ANEXO D.1 – Sem Ligação ao PC
$mod51
org 0000h
ljmp inicio
;****************************************************************************************************************************
configuracoes:
mov pcon, #80h ;configuracao porta serie
mov tmod, #021h
mov scon, #050h ;modo 0
mov ie, #00h
setb tr1 ;Inicia o TIMER 1
mov th1, #00FDH ;Valor Baud Rate=19200 bps
mov p1,#0ffh
mov p2,#0ffh
mov p0,#0ffh
mov 40h,#00h
mov 41h,#5Ah
mov 42h,#00h
mov 43h,#5Ah
mov 47h,#00h
mov 50h,#00h
mov 49h,#00h
mov 44h,#00h ;referencia
ret
;*******************************************************************************
*********************************************
referencia: ; procedimento que faz com que após se dar o reset a cabeça dê uma volta completa
; no eixo da azimute em busca do maior valor de luz. esse valor vai ser considerado como
mov r5, #14H
MOV R6, #0FFH ; a referência e a cabeça só irá responder para valores de luz acima desse valor. essa volta
MOV R7, #8CH
; de 360 graus é feita com a cabeça na posição de 45graus, pois é nesta posição que a
c1:
: cabeça tem um raio de acção maior
acall cima
acall conversao
acall maior
mov a,44h
clr c
subb a, 39h
jnc ref1
mov 44h, 39h
ref1:
acall delay
acall delay
acall delay
acall delay
acall delay
djnz r5,c1
C2:
acall esquerda1
acall conversao
acall maior
mov a,44h
clr c
subb a, 39h
jnc ref2
mov 44h, 39h
ref2:
acall delay
acall delay
acall delay
acall delay
acall delay
djnz r6, c2
C3:
acall esquerda1
acall conversao
acall maior
mov a,44h
clr c
subb a, 39h
jnc ref3
mov 44h, 39h
ref3:
acall delay
acall delay
acall delay
acall delay
acall delay
djnz r7, c3
ret
;****************************************************************************************************************************
inicial: ; procedimento que coloca a cabeça na posição 0graus após esta ter feito a busca da
mov r5, #14h
; referência
c6:
acall baixo
acall delay
acall delay
acall delay
acall delay
acall delay
djnz r5,c6
ret
;****************************************************************************************************************************
delay: ; atraso para ser usado sempre que necessário, neste caso nos sinais de controle do
mov r1,#0FFh
ciclo1: ; motor, nos sinais de conversão do ADC, etc...
mov r2,#0Ah
ciclo2:
djnz r2,ciclo2
djnz r1,ciclo1
ret
;****************************************************************************************************************************
envia_porta: ; procedimento que permite enviar o que quer queseja para o exterior, através da
mov sbuf, a
; porta série, utilizando o protocolo RS-232
envia_porta2:
jnb ti,envia_porta2
clr ti
ret
;****************************************************************************************************************************
recebe_porta: ; procedimento que permite receber o que quer que seja para do exterior, através da
mov a, sbuf ; porta série, utilizando o protocolo RS-232
recebe_porta2:
jnb ri,recebe_porta2
clr ri
ret
;****************************************************************************************************************************
canal0: ; procedimentos que servem para seleccionar qualo canal do ADC que se pretende
clr p2.4
clr p2.5 ; utilizar
clr p2.6
ret
canal1:
setb p2.4
clr p2.5
clr p2.6
ret
canal2:
clr p2.4
setb p2.5
clr p2.6
ret
canal3:
setb p2.4
setb p2.5
clr p2.6
ret
canal4:
clr p2.4
clr p2.5
setb p2.6
ret
canal5:
setb p2.4
clr p2.5
setb p2.6
ret
canal6:
clr p2.4
setb p2.5
setb p2.6
ret
canal7:
setb p2.4
setb p2.5
setb p2.6
ret
;****************************************************************************************************************************
converter: ; procedimento que permite fazer a conversão dossinais analógicos que vêm das LDR´s
clr p2.0 ; em valores digitais
nop
clr p2.1
nop
clr p2.3
nop
mov a,p0
setb p2.1
setb p2.3
setb p2.2
setb p2.0
ret
;****************************************************************************************************************************
cima: ; procedimento que faz com que a cabeça se movimente para cima no eixo da elevação
clr p1.1
clr p1.0
nop
nop
setb p1.0
nop
nop
clr p1.0
acall incremento
ret
;****************************************************************************************************************************
baixo: ; procedimento que faz com que a cabeça se movimente para baixo no eixo da elevação
setb p1.1
clr p1.0
nop
nop
setb p1.0
nop
nop
clr p1.0
acall decremento
ret
;****************************************************************************************************************************
direita: ; procedimento que faz com que a cabeça se mova para a direita no eixo da azimute
mov a,41h ; se a cabeça se encontrar no lado negativo, o sensor que no lado positivo
CLR C
subb a, 43h ; era para se mover para a direita agora é para a esquerda
jc esquerda1
CJNE A,#00H,VAI
mov a, 40h
CLR C
subb a, 42h
jc esquerda1
VAI:
jmp direita1
RET
;****************************************************************************************************************************
DIREITA1:
clr p1.3
clr p1.2
nop
nop
nop
setb p1.2
nop
nop
nop
clr p1.2
ret
;****************************************************************************************************************************
esquerda: ; procedimento que faz com que a cabeça se mova para a esquerda no eixo da azimute
mov a,41h ; se a cabeça se encontrar no lado negativo, o sensor que no lado positivo
CLR C
subb a, 43h ; era para se mover para a esquerda agora é paraa direita
jc direita1
CJNE A,#00H,VEM
mov a, 40h
CLR C
subb a, 42h
jc direita1
VEM:
jmp esquerda1
RET
;****************************************************************************************************************************
ESQUERDA1:
setb p1.3
clr p1.2
nop
nop
nop
setb p1.2
nop
nop
nop
clr p1.2
ret
;****************************************************************************************************************************
conversao: ; procedimento que converte os valores analógicos das LDR´s para digitais,
; até um máximo de 8 canais e os guarda em posções de memória do micro
acall canal0
acall converter
mov 30H,a
acall canal1
acall converter
mov 31H,a
acall canal2
acall converter
mov 32H,a
acall canal3
acall converter
mov 33H,a
acall canal4
acall converter
mov 34H,a
acall canal5
acall converter
mov 35H,a
acall canal6
acall converter
mov 36H,a
acall canal7
acall converter
mov 37H,a
ret
;****************************************************************************************************************************
maior: ; procedimento que determina qual o sensor que está a captar mais luz e
mov a,30h
mov r1,31h ; guarda esse valor numa posição de memória
clr c
subb a,r1
jc um
mov 38h,#0d
mov a,30h
mov 39h,a
jmp dois
um:
mov 38h,#1d
mov 39h,r1
dois:
mov a,32h
mov r1,39h
clr c
subb a,r1
jc tres
mov 38h,#2d
mov a,32h
mov 39h,a
tres:
mov a,33h
mov r1,39h
clr c
subb a,r1
jc quatro
mov 38h,#3d
mov a,33h
mov 39h,a
quatro:
mov a,34h
mov r1,39h
clr c
subb a,r1
jc cinco
mov 38h,#4d
mov a,34h
mov 39h,a
cinco:
mov a,35h
mov r1,39h
clr c
subb a,r1
jc seis
mov 38h,#5d
mov a,35h
mov 39h,a
seis:
mov a,36h
mov r1,39h
clr c
subb a,r1
jc sete
mov 38h,#6d
mov a,36h
mov 39h,a
sete:
nop
ret
;****************************************************************************************************************************
incremento: ; procedimento que incrementa uma posição de memória sempre que a cabeça
MOV a, 41h
cjne a,#0ffh,zero ; se mova para cima, para depois se conseguir saber se esta se encontra no lado positivo
mov 41h,#00h
inc 40h ; (maior que 90) ou no lado negativo (menor que 90)
jmp fim
zero:
inc 41h
fim:
nop
ret
;****************************************************************************************************************************
decremento: ; procedimento que decrementa uma posição de memória sempre que a cabeça
mov a,41h
cjne a,#00h,igu ; se move para baixo, para depois se conseguir saber se esta se encontra no lado positivo
mov 41h,#0ffh
DEC 40h ; (maior que 90) ou no lado negativo (menor que 90)
jmp fim2
igu:
DEC 41h
fim2:
nop
ret
;****************************************************************************************************************************
procura: ; procedimento que faz com que a cabeça após 9,55s sem captar nenhum valor de luz
mov 48h, 44h
MOV R6, #0FFH ; acima da referência, executa uma volta de 360graus em procura de um valor de luz
MOV R7, #8CH
; superior á referência
C8:
inc 50h
acall esquerda1
acall conversao
acall maior
mov a,48h
clr c
subb a, 39h
jnc ref6
mov 48h,39h
mov 49h,50h
ref6:
acall delay
acall delay
acall delay
acall delay
acall delay
djnz r6, c8
C9:
inc 50h
acall esquerda1
acall conversao
acall maior
mov a,48h
clr c
subb a, 39h
jnc ref5
mov 48h, 39h
mov 49h, 50h
ref5:
acall delay
acall delay
acall delay
acall delay
acall delay
djnz r7, c9
ret
;****************************************************************************************************************************
certa: ; procedimento que coloca a cabeça na posição de45 graus ou de -45graus
mov a, #59h ; dependendo do lado onde esta se encontra, antes de esta executar o procedimento
clr c
subb a, 41h ; de procura de luz
jnc certa3
certa1:
mov a, #77h
clr c
subb a, 41h
jnc certa5
mov a, 41h
mov 51h, #77h
clr c
subb a, 51h
mov r5, a
certa2:
acall baixo
acall delay
acall delay
acall delay
acall delay
acall delay
djnz r5,certa2
mov 41h, #78h
ljmp certa9
certa5:
mov r7, a
certa6:
acall cima
acall delay
acall delay
acall delay
acall delay
acall delay
djnz r7,certa6
mov 41h, #78h
ljmp certa9
certa3:
mov a, #45h
clr c
subb a, 41h
jnc certa7
mov a, 41h
mov 51h, #45h
clr c
subb a, 51h
mov r6, a
certa4:
acall baixo
acall delay
acall delay
acall delay
acall delay
acall delay
djnz r6,certa4
mov 41h, #46h
ljmp certa9
certa7:
mov r7, a
certa8:
acall cima
acall delay
acall delay
acall delay
acall delay
acall delay
djnz r7,certa8
mov 41h, #46h
certa9:
nop
ret
;****************************************************************************************************************************
inicio: ; Programa Principal:
acall configuracoes ; é feita a conversão dos valores das LDR´s e depois de acordo com esses valores
acall referencia
acall inicial ; o microcontrolador vai dar a indicaçãoá cabeça para onde esta se deve mover.
; ou seja, se a diferença de valores entre os dois pares de sensores fôr menor que 5
inicio1:
; a cabeça está centrada, se fôr superior a 5 o micro vai dar indicação para a cabeça
mov 47h, #00h
mov 50h,#00h ; se mover na direcção ou nas direcções do sensor do par de sensores que tiver a
inicio4: ; captar maior valor de luz.
acall conversao
acall maior
; por outro lado, sempre que a cabeça nao captar um valor de luz superior á
nop
; referência uma posição de memória vai sendo incrementada, para que depois o
mov a, 39h
clr c ; micro dê indicação á cabeça para esta executar o movimento de procura de luz
subb a, 44h
jc inicio5
quat:
mov a, 30h
clr c
subb a, 34h
jc quat1
mov 52h, #5d
clr c
subb a, 52h
jc lado
jnc ci
quat1:
mov a, 34h
clr c
subb a, 30h
mov 52h, #5d
subb a, 52h
jc lado
jnc ba
lado:
mov a, 33h
clr c
subb a, 31h
jc quat3
mov 52h, #5d
clr c
subb a, 52h
jc inicio1
jnc dir
quat3:
mov a, 31h
clr c
subb a, 33h
mov 52h, #5d
clr c
jc inicio1
jnc esq
ci:
mov a, 39h
clr c
subb a, 44h
jc inicio2
mov a,#174d
clr c
subb a, 41h
jc inicio1
acall cima
acall delay
acall delay
acall delay
acall delay
acall delay
ljmp lado
inicio5:
ljmp inicio2
ba:
mov a, 39h
clr c
subb a, 44h
jc inicio2
mov a,#5d
clr c
subb a, 41h
jnc inicio6
acall baixo
acall delay
acall delay
acall delay
acall delay
acall delay
ljmp lado
inicio6:
ljmp inicio1
dir:
mov a, 39h
clr c
subb a, 44h
jc inicio2
acall direita
acall delay
acall delay
acall delay
acall delay
acall delay
ljmp inicio1
esq:
mov a, 39h
clr c
subb a, 44h
jc inicio2
acall esquerda
acall delay
acall delay
acall delay
acall delay
acall delay
ljmp inicio1
inicio2:
inc 47h
acall delay
acall delay
acall delay
acall delay
acall delay
acall delay
mov a, #250d
clr c
subb a, 47h
jc inicio3
ljmp inicio4
inicio3:
acall delay
acall delay
acall delay
acall delay
acall delay
mov 49h,#00h
acall certa
acall procura
mov a, #01h
clr c
subb a, 49h
jc inicio9
ljmp inicio1
inicio9:
mov r6, 49h
C10:
acall esquerda1
acall delay
acall delay
acall delay
acall delay
djnz r6, c10
ljmp inicio1
end
ANEXO D.2 – Com ligação ao PC
$mod51
org 0000hljmp inicio
;*****************************************************************************configuracoes:
mov pcon, #80h ;configuracao porta serie SMOD-1 para 19200 bpsmov tmod, #021hmov scon, #050h ;modo 0mov ie, #00hsetb tr1 ;Inicia o TIMER 1mov th1, #00FDH ;Valor Baud Rate=19200 bps
mov p1,#0ffh
mov p2,#0ffhmov p0,#0ffh
ret
delay:mov r1,39h
um:mov r2,#0Ah
;////////////////////////////////////////////////////////////////dois:
djnz r2,doisdjnz r1,um
ret
envia_porta: ;enviar para a porta serie mov sbuf, a
envia_porta2:
jnb ti,envia_porta2 clr ti
ret
recebe_porta: ;receber da porta serie
mov a, sbuf
recebe_porta2:
jnb ri,recebe_porta2 clr riret
;canais do ADC
canal0:clr p2.4 clr p2.5 clr p2.6
ret
canal1:setb p2.4 clr p2.5 clr p2.6
ret
canal3:setb p2.4 setb p2.5 clr p2.6
ret
canal4:clr p2.4 clr p2.5 setb p2.6
ret
;realização da conversão
converter:
clr p2.0
nop
clr p2.1
nop
clr p2.3
nop
mov a,p0
setb p2.1setb p2.3setb p2.2setb p2.0
ret
;movimentoscima:
clr p1.1clr p1.0acall delaysetb p1.0acall delayclr p1.0
ret
baixo:setb p1.1clr p1.0acall delaysetb p1.0acall delayclr p1.0
ret
direita:clr p1.3clr p1.2acall delaysetb p1.2acall delayclr p1.2
ret
esquerda:setb p1.3clr p1.2acall delaysetb p1.2acall delayclr p1.2
ret
;conversão dos quatro canais utilizadosconversao:
acall canal0acall convertermov 30H,a
acall canal1acall convertermov 31H,a
acall canal3acall convertermov 33H,a
acall canal4acall convertermov 34H,a
ret
; enviar para o PC os valoresenvdados:
mov a,30hacall envia_porta
mov a,31hacall envia_porta
mov a,33hacall envia_porta
mov a,34hacall envia_porta
ret
;*****************************************************************************
inicio:
acall configuracoes
acall recebe_porta
inicio1:
acall conversao
acall envdados
acall recebe_porta
CJNE a,#'1',ciljmp inicio1
;movimento em elevaçao
ci:cjne a,#'2',baacall delayacall cima
ljmp segundo
ba:cjne a,#'3',diracall delayacall baixo
ljmp segundo
;movimento em azimute
segundo:acall recebe_porta
CJNE a,#'1',ciljmp inicio1
dir:cjne a,#'4',esqacall delayacall direita
ljmp inicio1
esq:cjne a,#'5',inicio1acall delayacall esquerda
ljmp inicio1
end
ANEXO E – Programa em Visual Basic
Form1 - 1 Dim recebeu As BooleanDim max As VariantDim indice As VariantDim buffer() As ByteDim inicio As BooleanDim resposta As ByteDim espera As BooleanDim fimciclo As BooleanDim reaccao As IntegerDim ficheiro As VariantDim referencia As IntegerDim velocidade As Integer
Private Sub Command1_Click()
Dim um As IntegerDim dois As IntegerDim tres As IntegerDim quatro As IntegerDim canaux As Integer
Dim enviar As VariantDim posicaoY As Integer
posicaoY = 80
' abrir ou criar caso não exista i ficheiro dados.txt Open "C:\DADOS.txt" For Output Shared As #1
fimciclo = False' informação para o micro começar a enviar os dados MSComm1.Output = "i" Do' teste para sair do programa If fimciclo Then Exit Do End If ' fazer uma espera para que os motores possam responder atempadamente Timer1.Interval = velocidade Timer1.Enabled = True espera = False Do If espera = True Then Exit Do End If DoEvents Loop
Form1 - 2 inicio = True Do If recebeu = True Then recebeu = False ' Mostrar valores recebidos Text1.Text = buffer(0) Text2.Text = buffer(2) Text3.Text = buffer(4) Text4.Text = buffer(6) um = buffer(0) dois = buffer(2) tres = buffer(4) quatro = buffer(6) ' Calculo da diferenca dos pares de valores Text7.Text = um - quatro Text8.Text = dois - tres ' guardar para ficheiro o valor das subtracções Write #1, um - quatro; dois - tres If um < referencia Then um = referencia End If If dois < referencia Then dois = referencia End If If tres < referencia Then tres = referencia End If If quatro < referencia Then quatro = referencia End If
' calculo do caracter a enviar para o micro fazer actuar os motores If Abs(um - quatro) > reaccao Then If um < quatro Then posicaoY = posicaoY + 1 enviar = "3" GoTo segundo Else
Form1 - 3 posicaoY = posicaoY - 1 enviar = "2" GoTo segundo End If End If enviar = "1" End If
segundo:
Text9.Text = posicaoY ' Testar se estamos nos limites da elevação If posicaoY < 1 Then enviar = "1" posicaoY = posicaoY + 1 End If If posicaoY > 159 Then enviar = "1" posicaoY = posicaoY - 1 End If If posicaoY < 80 Then canaux = dois dois = tres tres = canaux End If If Abs(dois - tres) > reaccao Then If dois < tres Then If enviar = "1" Then MSComm1.Output = "5" Exit Do End If If enviar = "2" Then MSComm1.Output = "9" Exit Do End If If enviar = "3" Then MSComm1.Output = "8" Exit Do End If Else If enviar = "1" Then MSComm1.Output = "4" Exit Do End If
Form1 - 4 If enviar = "2" Then MSComm1.Output = "6" Exit Do End If If enviar = "3" Then MSComm1.Output = "7" Exit Do End If End If End If If enviar <> "1" Then Form2.Timer1.Interval = 1 Form2.Timer1.Enabled = True End If MSComm1.Output = enviar Exit Do DoEvents Loop DoEvents Loop Close #1End Sub
Private Sub Command2_Click() ' parar a execução do programa fimciclo = True
End Sub
Private Sub Command3_Click() ' Sair do programa End
End Sub
Private Sub Command4_Click() ' mudar do form 1 para o form 2 Form2.Show Form1.Hide
Form1 - 5
End Sub
Private Sub Form_Load() ' Abrir a porta serie e inicializar variaveis MSComm1.PortOpen = True inicio = False Text5.Text = reaccao Text6.Text = referencia VScroll1.Value = 5 VScroll2.Value = 200 VScroll3.Value = 50
End Sub
Private Sub MSComm1_OnComm() Dim sMessage As String ' guardar o que vem da porta serie para a variavel buffer() Select Case MSComm1.CommEvent Case comEvReceive buffer() = MSComm1.Input recebeu = True End Select 'SetStatus (sMessage), False
End Sub
Private Sub Timer1_Timer() ' esperar pelo timer espera = True
End Sub
Private Sub VScroll1_Change() ' Actualizar o valor da sensibilidade reaccao = VScroll1.Value Text5.Text = reaccao
End Sub
Private Sub VScroll2_Change() ' Actualizar o valor de referencia referencia = VScroll2.Value Text6.Text = referencia
End SubPrivate Sub VScroll3_Change() ' Actualizar a frequencia de trabalho
Form1 - 6 velocidade = VScroll3.Value Text10.Text = velocidade
End SubPrivate Sub Form_Resize() ' Para não se alterar o tamanho da janela do programa Form2.Height = 9200 Form2.Width = 11500 End Sub
Form2 - 1 Dim y_seguinte1, y_seguinte2 As LongDim y_actual1, y_actual2 As LongDim num As IntegerDim escala As Integer
Private Sub escalatensao() escala = Combo2.Text lblV1.Caption = 1 * escala lblV2.Caption = 2 * escala lblV3.Caption = 3 * escala lblV4.Caption = 4 * escala lblV5.Caption = 5 * escala lblV6.Caption = 6 * escala lblV7.Caption = 7 * escala lblV8.Caption = 8 * escala lblV9.Caption = 9 * escala lblV10.Caption = 10 * escala lblV_1.Caption = -1 * escala lblV_2.Caption = -2 * escala lblV_3.Caption = -3 * escala lblV_4.Caption = -4 * escala lblV_5.Caption = -5 * escala lblV_6.Caption = -6 * escala lblV_7.Caption = -7 * escala lblV_8.Caption = -8 * escala lblV_9.Caption = -9 * escala lblV_10.Caption = -10 * escalaEnd Sub
Private Sub Combo1_Click() num = 0 y_actual1 = 4826 y_actual2 = 4826 Cls End Sub
Private Sub Combo2_Click() num = 0 y_actual1 = 4826 y_actual2 = 4826 Cls escalatensaoEnd Sub
Private Sub Form_Load() ' Inicialização das variaveis
Form2 - 2
num = 0 y_actual1 = 4826 y_actual2 = 4826 Combo1.AddItem "1" Combo1.AddItem "2" Combo1.AddItem "5" Combo1.AddItem "10" Combo1.AddItem "15" Combo1.AddItem "20" Combo1.AddItem "30" Combo1.AddItem "40" Combo1.Text = 10 Combo2.AddItem "1" Combo2.AddItem "2" Combo2.AddItem "5" Combo2.AddItem "10" Combo2.Text = 5 escalatensao End SubPrivate Sub poevalor()Dim vert As IntegerDim hori As IntegerDim color1, color2, grossura1, grossura2 As Integer
'ler valores do form1 para mostrar no grafico
vert = Form1.Text7.Texthori = Form1.Text8.Text
'definir grossura da linha
grossura1 = 2grossura2 = 2
If vert < -10 * escala - 5 Then vert = -10 * escala - 5 grossura1 = 1End If
If vert > 10 * escala + 5 Then vert = 10 * escala + 5 grossura1 = 1End If
If hori < -10 * escala - 5 Then hori = -10 * escala - 5 grossura2 = 1End If
If hori > 10 * escala + 5 Then hori = 10 * escala + 5 grossura2 = 1End If
Form2 - 3
y_seguinte1 = 4826 - vert * 268 / escalay_seguinte2 = 4826 - hori * 268 / escala
If num >= 40 * Combo1.Text Then num = 0 ClsEnd If
If Abs((4826 - y_actual1) / (268 / escala)) < Form1.Text5 And Abs(vert) < Form1.Text5 Then color1 = 12 Else color1 = 4 End If If Abs((4826 - y_actual2) / (268 / escala)) < Form1.Text5 And Abs(hori) < Form1.Text5 Then color2 = 9 Else color2 = 1 End If
DrawWidth = grossura1 Line (1200 + 240 / Combo1.Text * num, y_actual1)-(1200 + 240 / Combo1.Text * (num + 1), y_seguinte1), QBColor(color1) y_actual1 = y_seguinte1
DrawWidth = grossura2 Line (1200 + 240 / Combo1.Text * num, y_actual2)-(1200 + 240 / Combo1.Text * (num + 1), y_seguinte2), QBColor(color2) y_actual2 = y_seguinte2 num = num + 1
End Sub
Private Sub Command1_Click()
' sai do form2 para o from1
Form1.Show Form2.Hide
End Sub
Private Sub Form_Resize()
' Serve para não se alterar o tamanho da janela do programa Form2.Height = 9200 Form2.Width = 11500
Form2 - 4 End Sub
Private Sub Timer1_Timer()
'actualiza o grafico poevalor
End Sub
ANEXO F – Lista de material
LISTA DE MATERIAL
Quantidade Referência /Descrição Valor 2 AT89C51 1 MX7828 1 MAX233A 2 SAA1042 8 BD248 5 7805 8 Resistência 10KOhm 1 Resistência 1KOhm 8 Resistência 150 Ohm 1 Resistência 470 Ohm 1 Condensador 47µF 1 Condensador 1µF 1 Condensador 100nF 2 Condensador 33pF 1 Cristal 11MHz 2 Zener 3,9 V 8 Born ligação de 3 entradas 5 Dissipador 1 Botão de pressão 1 Suporte físico 2 Contactos deslizantes 1 Cabo com ligação à porta série 2 Motor passo-a-passo unipolar 4 LDRs 1 Bola de plástico
ANEXO G – Desenho em Mechanical