PIC16F886 Pulldown inputs


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  1. #1
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    Default Re: PIC16F886 Pulldown inputs

    - So just to be clear - I'm driving the optos using the 2k to the anode, the output is the "collector" tied hi to a resistor - to the PIC w 5V. I'm not sure 100 ohms to the PIC would damage the PIC, but I dont think the opto would care?

    In any case - I'll use 10K like you suggest.. no real reason to use 100.
    My dad never liked you...

  2. #2
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    Default Re: PIC16F886 Pulldown inputs

    With 100 ohms from +5 to the collector of opto, you will force 50mA through opto. This is the absolute max according to the data sheet. It will lead sooner or later to the destruction of the opto.

    Please do use 10K from +5 to the collector of the opto and drive from the collector the PIC port. The emitter of the opto will be earthed.

    Everytime you feed current to the LED of the opto, the PIC port will be low and when the LED is off, port will be high.

    Ioannis

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