Stats

  • Locked Locked
  • Replies 3
  • Subscribers 64
  • Views 14135
  • Members are here 0
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

ADE-GXL optimization issue

hmcheema

Hello,

 I wish to run optimization for getting the maximum frequency tuning range of a VCO. This means that i need two frequencies corresponding to Vtune=0 V and Vtune=1.2V. (Vtune is the voltage applied to the varactors)

The optimization should then take the difference of the two frequencies and maximize it based on the parameters given.

To achieve this, i added two tests providing the two frequencies and naming them Freq0 and Freq1 but ADE-GXL does not allow to write an expression including outputs from two different tests.

 Is there a way to write an expression like Freq1-Freq0 and then add a specification to maximize it? Please see attached screenshot for reference.  

Kind help from the Cadence officials will be appreciated. Any other method which i can do?

Screen-shot of ADE-GXL setup

Free Filehosting At image upload

  • What you need is the calcVal() function. You can use calcVal("outName" "testName"). The easiest way is to bring up the calculator, and then drag from the ADE XL output pane - pick the output you wish to reference - and then drag into the calculator input buffer. This will automatically generate the calcVal() expression for you. Then you can have an output on one of the two tests which references the other test; ADE XL/GXL will take care of ensuring that the tests are run in the right order so that it can do the calculation.

    Regards,

    Andrew.

  • Thanks Andrew and Firas Barakat who sent a detailed email to answer the question. I am able to combine the two outputs of different tests in one expression.

    Kind Regards.

  • Comment from my side: CalcVal is a fine method but often even this can be easily avoided often by just rearranging the testbench a bit. In your case, you currently do e.g. two tests, each doing a pss with different vtune. A better setup would be to run a swept-pss just with vtune swept. In your case this method is faster and more reliable than calcVal. Bye Stephan

Community Guidelines

The Cadence Design Communities support Cadence users and technologists interacting to exchange ideas, news, technical information, and best practices to solve problems and get the most from Cadence technology. The community is open to everyone, and to provide the most value, we require participants to follow our Community Guidelines that facilitate a quality exchange of ideas and information. By accessing, contributing, using or downloading any materials from the site, you agree to be bound by the full Community Guidelines.