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Here are two variations on a CMOS op-amp, similar to the sample 2
stage one in Allen & Holberg's "CMOS Analog Circuit Design" text.
It is not an optimal design, just one to play with.  The results
are the same as Spice, as expected.

The files:
opamp-ol.ckt	open loop: op, ac, dc
opamp-vf.ckt	voltage follower: op, ac, dc, tran

We do a few extras, like a plot of Cgs(M7) vs. input voltage.  Try
that in Spice.

Then, there's another one.  An ac analysis at saturation.  Try that
in Spice.

Spice shows you everything, whether you like it or not, on an "op"
analysis.  You can't see them at all in any other.  But those values
are not constant.  They vary with the signals.  ACS will show you
(if you want) how they vary with the signal.