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  1. #1
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    Amplifier not working as per expectation

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    The amplifier works as a voltage follower. It takes 3.12V from the voltage divider, so it should give out 3.12V as it is an voltage follower but instead i am getting 1V. Can someone guide me on this..

    •   Alt21st April 2017, 06:54

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    Re: Amplifier not working as per expectation

    Circuit is incomplete. How is 10V supply grounded? Also what is Vcc?



    •   Alt21st April 2017, 07:11

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    Re: Amplifier not working as per expectation

    V- is connected to ground. VCC is 5V.



    •   Alt21st April 2017, 07:24

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    Re: Amplifier not working as per expectation

    Hi,

    your +INPUT seems to be floating. This is not allowed. It needs some reference to GND.

    Klaus



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    Re: Amplifier not working as per expectation

    Spare me for the incomplete circuit. I have checked the voltage at amplifiers input its 3.1V but at output its 1V.



    •   Alt21st April 2017, 14:13

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    Re: Amplifier not working as per expectation

    V- is connected to ground. VCC is 5V.
    Why don't sketch the complete circuit? Anyway, the circuit should output 3.1 V, the schematic doesn't show a problem. Use a multimeter to check node voltages against ground: Vcc, V+, non-inverting OP input.

    - - - Updated - - -

    O.K., either the amplifier is defective, pins are wrongly connected or the output is overloaded. Disconnect load to check.



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    Re: Amplifier not working as per expectation

    Hi,

    Use a multimeter to check node voltages against ground:
    If the +INPUT still is floating, then the voltage at this node may be 3.1V as long as a voltmeter is connected, but it may be any other voltage when voltmeter is disconnected.
    It simply is not defined.

    Klaus



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    Re: Amplifier not working as per expectation

    Your V- input must also connect to the battery negative.
    dotcom, Than I Guess I am Not wanted here either.



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