simulation of AC parameters

[lhlbluesky]

for a single-ended and a fully differential opamp, how to simulate their common-mode AC parameters, such as common-mode gain\bandwidth etc separately?
can anyone help me or give me the simulation circuit diagram,pls?

besides,for fully differential opamp, now sc common-mode feedback is commonly used. but how to simulate the common-mode parameters of the common-mode feedback loop(sc common-mode feedback)?and how to determine the two capacitor value in sc common-mode feedback circuit?

pls help me, thanks all for reply.

 

[lhlbluesky]

can anyone give me some advice?