Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
here is the transfer function of your circuit: H(s)=N(s)/D(s)
N(s)=(+ H3 H1)
D(s)=(+ H4 H3) + ( - H2 C2) s + (C2 C1) s^2
The negative sign in the denumerator indicates that something is wrong since all expressions in D(s) must be positive.
A visual inspection of the circuit shows that you have positive dc feedback (see the second unit) thereby inhibiting linear operation.
Please check the circuitry.
The second unit with 100% feedback acts as a grounded resistor (R=1/g2=1/H2) in parallel with X=1/sC1
With this in mind you can apply the classical rules for OTAs with Vout/Vin=g*Xload.
The whole circuitry is the OTA representation of the classical opamp lowpass configuration consisting of a damped and an undamped integrating device connected in a closed loop.