Geoffrey_Coram wrote on Mar 28th, 2007, 5:13am:Put in a "save" statement to get the capacitances:
save m1:all
You can also run an ac analysis with a swept dc bias
ac1 ac freq=0.1591549 dev=vd start=0 stop=1.8
which sets the frequency to 1/(2 pi) such that imaginary currents are exactly equal to the capacitances. (You do have to look out for internal resistors, though, which will distort the results.)
For *using* Spectre, the built-in help (spectre -help) is good enough for me; Ken did write the Designer's Guide to Spice and Spectre if you want to know more about the internal workings.
Yes, this is a very good tip, assuming the resistance is low. Also, you can use the CAPTAB option to get the node caps at an operating point. Is there any way to do a DC sweep and plot the CAPTAB results for a node, similar to the 'save m1:all' tip?