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Retrieve design variables using VAR() in both single and monte carlo run

RuneDS
I use the VAR() function to retrieve design variables in skill/ocean scripts for post processing. When running monte carlo simulations, the script wont work due to VAR("variable") returning a wave of variables. Is there a way to use VAR() or an equivalent function for getting design variables in scalar form without making separate scripts for single and monte carlo/sweeps?
  • Hi, Have you tried using the Ocean function desVar() ? The VAR function is rather old, so you may have a better chance with desVar. Hope it helps, Lawrence.

  • Hi Rune,

    Did you finally manage to use the VAR() function (or an equivalent one) in monte carlo runs?

    I have the same problem and I have not idea about how to proceed.

    Thanks!!!

  • Really? This should work. Which IC version and MMSIM version are you using?

    BTW, appending onto a 4 year old thread is probably not the smartest way of ensuring you get an answer (see the forum guidelines - the first post in each forum). You got lucky this time and I responded...

    Regards,

    Andrew.

  • Hi Andrew,

    First of all thank you for answering to such an old post. I agree appending an old post is not the best way, but it was the only one I found related to the same matter. For future post (this was actually my first one) I take your advice into account,.

    I am using IC6.1.6 with MMSIM 12.1. The issue is that in "single run, sweep and corners" simulation the VAR() function works well but not if I run monte carlo. I have tried to substitue the VAR() function by a numerical value (just as workaround) on monte carlo analysis and it works.

    Any idea?

    Regards,

    Antonio 

  • Hi Antonio,

    I just tried this (admittedly I wasn't using MMSIM12.1, but I don't think that would be relevant), and it worked fine for me. 

    So, two things:

    1. What is he complete expression  you're using that doesn't work?
    2. Which subversion of IC616 are you using (Help->About will tell you this).

    Regards,

    Andrew.

  • Hi Andrew,

    I am performing the dynamic characterization of a DAC using the "spectrumMeasurement" function to calculate ENOB, SNR, SINAD, THD,... For example, one of the expressions that does not work in monte carlo analysis is:

    spectrumMeasurement(VT("/Vout") t VAR("delay") VAR("TSTOP") VAR("numpoints") (VAR("fclk")/VAR("numpoints")) (VAR("fclk")/2) 0 "Cosine2" 0 0 10 "enob")

    My complete IC version is IC6.1.6.500.1

    Thanks for your time!

    Antonio

  • Hi Antonio,

    I have an example which is doing something similar (my expression isn't identical to yours, and I don't have the time to set it up to be exactly the same), but broadly speaking it's similar. Mine works OK - although I'm  using IC6.1.6.500.14 - yours is a pretty old ISR and maybe it was broken then.

    It ought to work - so I would suggest moving to the latest IC616 ISR, and if it's still not working, please raise this with customer support as it may be something specific to your setup which needs investigating and fixing.

    Regards,

    Andrew.

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