Hi,

I am using PSS and Pnoise to simulate a switch-cap circuit, which is used to behave as a DC feedback resistor for a AC-coupled amplifier. The SC circuit needs 4 clock phases. CK1 and CK2 are two non-overlapping clock phases. CK1d and CK2d are two slightly delayed clock phases of CK1 and CK2. If I use 4 seperate clock sources from analogLib, the simulation will give 5 times bigger noise voltage than one clock source with a specific non-overlapping clock generator. The PSS form will show 4 fundamental tones, even though all have the same frequency. Does it matter for the final noise calculation? Why?

Please shed some light if you know the cause. I want to make sure which result is correct. Thanks in advance for your explanation!

Regards,
Sapphire