Indicate the noise sources in the circuit and give an expression for the signal to noise ratio at the output given the signal to noise ratio at the differential input, if Rf == Rfdash. Solution Actuaaly in this circuit mainly used for reduce the noise (improve the signal to noise ratio) in this circuit mainly comes noise in Vcc supply . then we can improve the derivation is applying same inpput voltage in both inverting and non inverting signals. so this amplification difference noice is reduced. examle: here taken output voltage is V1: -Vsig + Vnoise V2: +Vsig + Vnoise Vd is : V2-V1 = 2Vsig Vc= 2Vnoise V0 = Ad.Vd+ Ac.Vc = Ad.@Vsig+ Ad/CMMR .2Vnoise.