Paul wrote on Feb 8th, 2006, 7:43pm:Hi,
As Steven says, both are Miller capacitors. I have seen schematics using C2 in the past, but I haven't seen a circuit using both capacitors at the same time. Notice that both nodes don't have the same conductance, so the pole expression in presence of both capacitors may be somewhat different. Would be interesting if someone had time to write the equations...
Paul
Hi Paul,
I think the circuit would introduce zeros in the response. If considering the Thevenin impedance looking from the drains of M15 and M19, the impedance will be similar to common-gate topology. At high-frequency, the feedback network becomes inductative. I guess in this respect, either of them is redundant.
Regards,
Steven