Draw and explain the Op-amp based subtractor
Working The subtractor circuit is a basic op-amp circuit whose output voltage is the difference between two input voltages.
In the above circuit, the two input voltages are V1 and V2.
The op amp is used in inverting mode, so gain of the amplifier is Rf / R
Output due to V2 alone = - Rf / R2
Output due to V1 alone = - Rf / R1
The output of the differential amplifier =Vo = - (Rf / R)( V1 - V2) if R1 = R2 = R.
When differential gain is 1, ie Rf = R,
the output voltage is Vo = (V2 – V1).