Hello all!!Originally posted in cdnusers.org by axp
I'm designing a bandpass filter using switched-cap (100Hz center frequency and Q=5 with two low-Q and one high Q biquad).
At typical case, the pss simulation converges well and the AC results are similar to what is expected.
However at corners, especially at lowest temperature, the pss simulation do not converge or converge with difficulty.
If pss finally converges, the AC results given are wrong and the transient results (of one period) that can be seen with pss, shows big oscillations (some signals go down to zero with a fixed
period). This issue is solved if opamps are replaced by ideal ones.
Also, this oscillation cannot be seen with traditional transient
Does anyone have some ideas on that issue?
Any idea is welcome.
Thks in advance