I am simulating a chopper stabilized opamp circuit in which I need to do noise analysis. As the biasing point is changing with time periodically, I need to do PSS analysis and for Noise PNoise analysis. As I am changing my minimum frequency of the signal beat frequency is getting changed but every time I am getting a peak in noise plot at 1KHz only. It is irrespective of all frequencies in circuit. In circuit signal frequency is around 500Hz and clock frequency is arounf 1MHz.
This peak is coming only at 1KHz only. What is wrong, being done by me during simulation ?
Please help.