Finite Gain Differential Amplifiers:

In the 3-port VCVS of Figure, if a potential divider is added at the input, the circuit of Figure is achieved for which we get :

V₁  =     (R₄/ R₃  + R₄)    e₁

Combining Eqs. (58) and (53), we get

V₀  = ( 1+ (R₂/R₁) /(   1+ (R₃/R₄)   e ^{-( R}₂ ^/R₁^{) V}₂ 

Figure: Finite Gain Differential Amplifier

Letting R₂ /R₁ = (1+ (R₂/R₁) /(1+ (R₃/R₄)   - K

The circuit realizes a K-gain differential amplifier for which the needed resistor values are found to be

R₂ = k R₁, R₄ = KR₃