Parametric Monte Carlo Analysis Cadence

[moammadhasan]

hi all!

I'm gonna use Monte Carlo Analysis to find standard deviation for input Offset of a latched Comparator using icfb 5.10.41_USR5.90.69. the goal is to plot it against a voltage value called Common Mode Voltage. It is to some extent a parametric Monte Carlo analysis. But it seams this version cant sweep any parameter. It is as if I need to run the "tools> Parametric Analysis" of "ADE" for Monte Carlo!!! would anyone help?

the other question is that: what does "stddev" function ADE Calculator really do?!! when I use tsmc 0.18rf Library file for mismatched models of the Mosfets, I found this "stddev" calculates some standard deviation for any node voltage without Mont Carlo or even some Parametric Analysis. Is it reasonable? "stddev" even calculated standard deviation over the swept voltage mentioned above, i.e standard deviation over a voltage instead of iterations!!!!! what does it mean?

sorry for my weak English & thanks a lot for any response......

 

[dick_freebird]

One option is to use Ocean to run the nested MC and PA.
The GUI interface is craptastic for anything besides what
Cadence bothered to put in the can.

Another option is to simply create N Monte Carlo runs,
each at a different common mode voltage of interest.
Export the data from each to a file, pull them all into a
spreadsheet and grind the data as you see fit. This can
also give you 1/N the total solution time if you farm it
out to N different machines.

stddev may give you an answer even when it is given
non-gaussian-statistical data. What the use of that is,
might be nil. Certainly if you took the standard deviation
of deterministically generated points, it's likely to be
garbage in any statistical sense.