using calcVal with parametric parametric sweep

Dear Svilen,

Svilen64 said:

All this works if I run a single corner simulation. However, I tried running a variable sweep and expected that the calcVal values will pass among the three test for the relevant sweep points. For example, for sweep point 1 I expected that the expression from test 1 will go to the calcVal definition in test 2 and 3 for the same sweep point. And similarly for the rest of the sweep points. From what I read I defined it like that calcVal("name" "test name" ?matchParams "all") but what happens is the expressions using the calcVal in tests 2 and 3 return nil.
Is it the right approach for what I am trying to do?

Unless i overlooked it in your question, I'm not sure if you are doing a global or local variable sweep. The manner in which calcVal() must be used is dependent on the presence of a local or global sweep. If you are doing one or more global variable sweep(s), the use of ?matchParams is not necessary and the values defined as calcVal() variables will pass for the same corner (or sweep) between tests exactly as I believe you want. If you are doing a local variable sweep, the use of additional parameters to calcVal() may b required in order to indicate which specific value to pass.

This is discussed in some detail in the Cadence RAK entitled "Using calcVal and its Arguments with Virtuoso ADE Assembler".

Shawn

Hi Shawn,

Thanks a lot for replying.
I am using a local variable sweep, not global. And when setting up the simulation I was referring the document you mentioned. That's how I came to know about setting the matchParams "all"

Thanks

Svilen

Svilen,

It's almost certainly best to handle this via customer support (please submit a case after logging in). We'll need to see the IC version you're using (that's more important than the Spectre version in this case) and also precisely how the sweeps and calcVals are set up.

Andrew

Hi Andrew,

The version is ICADVM20.1-64b.500.31
Do different versions have different functionality for calcVal?

There have been improvements and fixes to calcVal over time - it's a complex thing to handle every scenario and there have been gaps in functionality. However, you're using a fairly recent ISR of ICADVM20.1 so that should be OK - that was what I was trying to check (maybe you had been using a very old version).

Please contact customer support so you can show your precise simulation setup to help identify what is wrong, either with calcVal itself or with your usage of it. Maybe we can find a workaround that way - but seeing the simulation setup is key to this.

Andrew