The Inverting amplifier

vo/vi = -Rf/R1

Determination of gain formula.

The Inverting Summing Amplifier

As many additional inputs as wanted can be added. vo = -Rf/R1 v1 -Rf/R2 v2 -Rf/R3 v3

For an ideal op-amp:
The output due to each input is: von = -Rf/Rn vn

© Copyright 1996 New Mexico Institute of Mining and Technology