Hi, I need to determine the transfer function Vout/Vin. A traditional differential amplifier transfer function without the 2.2uF on the input side would be G1 = (Z2/Z1)*Vin, where Z2 = (2.2uF // 150kOhms) and Z1 = 450kOhms + 150kOhms . I am having some trouble to model de 2.2uF input capacitor. The output filter stage (Rout = 10k and Cout = 2.2uF) transfer function is G2 = 1/(sRC+1). The total transfer function without the input capacitor is G1*G2. How do I deal with the input capacitor filter stage (2.2uF connecting both inputs after the 450k resistor)?
I believe this is the correct transfer function for the input filter, it gives the 1/4 gain with some low pass dynamics Vout/Vin = G(s) = (1/4)*2.02/(s + 2.02)
Second stage considering only the op amp ( (2.2uF//150kOhms)/(150kOhms) ratio ): G1(s) = 3.03/(s + 3.03)
Output stage considering the RC filter: G2 = 1/(sRC+1) = 45.45/(s + 45.45)