How to know a special run montecarlo simulation variance

You can do this in IC61X in ADE XL. Simply go over the particular iteration number in the outputs pane, and do Right Mouse->Annotate->...

Regards,

Andrew.

Thanks for your reply. But the problem is that the cadence I use is version 5.1.41.

Now I can save a special run simulation result in montecarlo simulation window "analog statistical

analysis", then load it in "virtuoso analog design environment" windows. By using printing, i can print

the node voltage and  DC operating point. But the annotate does not work, especially I want to know 

each component real parameters used in the given montecarlo run, such as resistor value, capacitor

value and W L of transistors.

Andrew Beckett said:

You can do this in IC61X in ADE XL. Simply go over the particular iteration number in the outputs pane, and do Right Mouse->Annotate->...

Regards,

Andrew.

That's why we have the Community Guidelines - so people don't waste time giving you answers you can't use; I had no idea which version you were using.

There is no support for annotation of operating point data from monte carlo iterations in IC5141. You can print the info, or use the results browser to access the data, but no annotation I'm afraid. One of the numerous reasons to move to IC61X if you can (IC5141 was released 7 years ago, so understandably there have been some major advances since then).

Regards,

Andrew.

 Sure, in the analog statistical analysis window,

Number of runs: 1

starting Run#: 80.

That is it.

panchkapunch said:

Could you please tell me how you run only iteration no. 80.I am using version 5.1.41 as well

Oh, I also want to know if we can do that in old version cadence :(

panchkapunch said:

Thanks...but what i wanted to do was test whether my circuit can be 'trimmed' back to desired output. So, I want to run the varied process parameters as in run 80 and change a design variable (say a resistor) to see if i get back the desired output at this process corner...

There is no UI support in IC5141 ADE for the seed in monte carlo. There is a .cdsenv setting which alters it:

 asimenv.monte seedValue string "1"

However, as you pointed out, it defaults to 1 so the runs will be consistent. The same is true for Monte Carlo in ADE XL in IC61X - it defaults to 12345.

If you're only changing a design variable, the process (and indeed mismatch) parameters should match so run 80 should be the same each time - as far as the models are concerned. Even if you're changing the circuit topology, then process variables won't change, but mismatch might well do because the random number generator will be called in a different order or a different number of times.

Best Regards,

Andrew.