Unity gain buffer

Discussion in 'General Electronics Chat' started by Anestis88, Nov 10, 2014.

  1. Anestis88

    Thread Starter New Member

    Aug 9, 2011
    19
    2
    Hello
    I want to use a unity gain buffer to drive an ADC. However, I want to ask which is the difference (if any) between the first and the second op amp. Do they act the same ? Buffer.jpg
     
  2. BobTPH

    Active Member

    Jun 5, 2013
    785
    114
    No.

    The first is a differential amplifier. The second is a unity gain buffer.

    Bob
     
  3. Anestis88

    Thread Starter New Member

    Aug 9, 2011
    19
    2
    Ok I understrand now. So in my case that I have a differential signal, I suppose that the first one with all the resistors equal will be fine.
     
  4. Veracohr

    Well-Known Member

    Jan 3, 2011
    552
    76
    If you use equal resistors you'll have a gain of 3. For unity gain, use R1=R2=1.5Rg, Rf=Rg.
     
Loading...