Doing a simulation of neural network to measure output waveform of U2, but there is no change in the output waveform is always of U2, the output voltage is not operational amplifier saturation voltage, don't know what went wrong

FX is not used, is the suspended state, I was in my circuit diagram on the inside, there is no added



This is the circuit diagram of literature

This is given in the literature of the output waveform

This is my part of the circuit with PSpice software

This is the result of simulation out I


Then I put the U2 there capacitance deleted, found that after delete and delete output wave are the same as before, U2 have played an important role in an amplifier directly, not play the role of integrated amplifier