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    What is minimum input voltage which LM741 op-amp can amplify when used as amplifier?

    what is minimum input voltage which LM741 op-amp can amplify when used as an amplifier

    I tried to find this in datasheet but there is maximum value but not the minimum.May be its given in the form of some other parameter or i am unable to understand so plz help.

    actually my pressure sensor MPXM2202AS can give me output proportional to input pressure in the range of 0 mV to 20 mV.This a differential output voltage.I want to use LM741 to amplify this output.

    Any suggestion or consideration to be taken care of for this amplification

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    lm741 op amp circuits

    It should be (Supply Voltage)/Gain.



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    lm741 operational amplifier

    There is no such a thing like "minimum input voltage". Opamps are linear devices and will amplify any input voltage.
    However, because of temperature drifts, bla, bla ,bla .. with opamps like 741 one should avoid using them with voltages below "certain" level. I wouldn't use 741 for amplifying signals below,say, 1mV. Try to employ more contemporary common opamp and (LM)358 (bipolar) wouldn't be wrong choice as it can operate of single supply starting from 0V at the input..
    Other option would be CA3140(FET), also working very well with single supply and behaving good at 0V input..



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    lm741 calculation

    "IanP" gave correct answer.
    I can only add that you should define your needs and on this basis you can determind if 741 is good to your application.
    Example:
    You want to have the signal to noise ratio (for the AC component) above 40 dB ,
    equivalent voltage noise at amplifier input is 1 uV (this voltage is generated by the silicon).
    You can "easily" calculate, that you signal shod be at least 100uV..
    I put "easy " in quotation mark, because in your calculation you should include source resistance , OP voltage noise and OP current noise, frequency range....and few other parameters that did not came to my mind at the moment.

    The same is in case of DC offset, thermal stability, common mode rejection and so on...



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