summing and differential op-amp

1.  Summing Amplifier
Differential Amplifier
BY GROUP 8th

2. Two types
Inverting summing amp.
Non inverting summing amp

3. Much like the inverting
amplifier, but with two input
voltages
1. non inverting input
still held at ground
2. I1 , I2 and I3 are added
together to run through
Rf
So, we get the (inverted)
sum:
Vout = Rf(V1/R1 + V2/R2
+ V3/R3)

11. VO=Rf/R1(V1-V2)
By using superposition theorem we
calculate this formula for diffe.op-amp

13. Example

14.  Audio mixer(to add signals of equal gain)
 Digital to analogue converter
 Led modulation circuit

15.  Generally, we use differential amplifier that
acts as a volume control circuit.
 The differential operational amplifier can be
used as an automatic gain control circuit.
 Some of the differential operational
amplifier can be used for Amplitude
modulation.