Inverting Operational Amplifier

Make an inverting amplifier with an op-amp

Brief Summary
A low amplitude (80mV) sinusoidal wave is amplified using a simple Op-Amp, and its gain is calculated by precisely fitting the input and output waveforms using Numpy. This is tallied with the expected gain based on the popular theoretical formula.
July 05, 2017
Jithin B.P.

Quick Start

The schematic is wired as shown in the diagram below. Ri = 1k and Rf = 10k. The WG amplitude is set to 80 mV, you may try a 1 volt input to observe the clipping of the the output, since it will exceed the op-amp supply voltage of +/- 6 volts.

Photograph: Inverting Amplifier with an Opamp

Screenshot of the UI

Screen shot of the oscilloscope program showing inputs and output of an Inverting Amplifier. Theoretical Gain is -10 ExpEYES17: Opamp- inverting amplifier


  • Calculate the gain by fitting A1, and A2 by enabling the check-boxes next to them. gain = output/input
  • What is the gain if Rf < Ri .

Write Python Code

This experiment can also be done by running this Python Code.

import eyes17.eyes
p =

from pylab import *

p.set_pv1(1.35) # will clip at 1.35 + diode drop 
t,v, tt,vv = p.capture2(500, 20) # captures A1 and A2

xlabel('Time(mS)') ylabel('Voltage(V)')
plot([0,10], [0,0], 'black')

plot(t,v,linewidth = 2, color = 'blue')
plot(tt, vv, linewidth = 2, color = 'red') 

Op-amp inverting python code output