Op amp integrator

Discussion in 'General Electronics Chat' started by Gibson486, Dec 19, 2013.

  1. Gibson486

    Thread Starter Active Member

    Jul 20, 2012
    I was looking at op amp integrators....

    I found this site...


    I am kind of confused as to what R4 and R7 does in the circuit. Is it just there to make sure it is no referenced at zero (it shifts it up to a non zero center value on the scope)?
  2. GopherT

    AAC Fanatic!

    Nov 23, 2012
    They should be equal to the parallel resistance of the two resistors connecting to the inverting input to balance the offset. They are not really needed for high input impedence op amps. A wire from non-inverting input to ground is all that is needed.