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    Positive to Negative Logic

    Hi,

    I have a circuit which reads 24V, scales down to controller compatible voltage and controller reads HIGH when 24V is connected, else 0 when 0V is connected. Essentially its a positive logic. 24V = HIGH and 0V = LOW. If I want to convert the same circuit to a NEGATIVE LOGIC i.e 24V = LOW and 0V = HIGH, what would be simplest way without changing much of hardware circuitry.

    I have attached the part of the circuit. Basically I want a inverted LOGIC at output of pin 7 of the opamp.

    Regards
    Shome

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    Re: Positive to Negative Logic

    The obvious/trivial answer is change the opamp to an inverting configuration.

    Or, if your input is floating, just swap the return and signal.


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  3. #3
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    Re: Positive to Negative Logic

    Quote Originally Posted by barry View Post
    The obvious/trivial answer is change the opamp to an inverting configuration.

    Or, if your input is floating, just swap the return and signal.

    Thanks for the reply.
    Last edited by soumen21; 13th January 2020 at 11:28.



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