This is the last article in the series of differential op-amp circuits. This is one of the most important operational amplifier circuits and hence it was saved for the last.
The speciality of using differential amplifier is that it uses both inverting and non-inverting input terminal to amplify one input signal, while other is fastened to ground
Let me remind you that the output is equal to the difference of the input, and as said before it is the special case of operational amplifier where you choose the amplification by choosing the various values of resistance.
Let begin the operation by seeing the output voltage from differential amplifier
DIFFERENTIAL AMPLIFIER CIRCUIT USING OP-AMP
It actually amplifies the variation between two voltage signals with a gain. As you can see, it is very much evident that by varying the resistance value you could amplify the signal to a greater extent. For example, choosing lower value of R1 and higher values of R3 will result in higher amplification of voltage signals.
- To amplify the signals
- Active anti-alias filtering
- Third – order low pass filter
- We can get unity gain by using equal values of resistance