Hi Sheldon,
Thanks fdr your detailed reply. I did some thinking and I agree with you that the histogram method
does not have such a big limitation as far as nonmonotonicity is concerned, unless the errors are really
really bizarre, almost unphysical in nature.
And when I speak of the histogram method, I am speaking of a ramp-based histogram method.
One uses sinewaves in real life because precise ramps are almost impossible to generate. However,
in a simulation setup, that is trivial. This cuts down the number of points seriously because the
points on a ramp have uniform density.
I will think about Verilog-AMS, but I think that MATLAB is much better if one is only modelling
higher-level issues, such as impact of capacitor mismatch or finite opamp gain. In MATLAB, one can
avoid the trouble of generating the ramp in time-domain but generate a virtual ramp in the input-domain
by using a vector input. As MATLAB is very good at vector match, calculating the output for 10^5 input
points does not take so much more time than calculating it for 10^3, as everything runs in parallel.
I am able to simulate random mismatch variation for 1000 runs in a matter of 1 hour or so
Regards
Vivek