• Skip to main content
  • Skip to search
  • Skip to footer
Cadence Home
  • This search text may be transcribed, used, stored, or accessed by our third-party service providers per our Cookie Policy and Privacy Policy.

  1. Community Forums
  2. Custom IC Design
  3. I installed a new GF55lpx PDK, and I when I run PVS-QRC...

Stats

  • Locked Locked
  • Replies 1
  • Subscribers 125
  • Views 13498
  • 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

I installed a new GF55lpx PDK, and I when I run PVS-QRC, I get incorrect models name in Spectre netlist and in av_extracted view

smartind
smartind over 8 years ago

I'm setting up a new PDK and I have PVS-LVS working.


When I generate a QRC(13.2) exrtacted view,  I get parasitic- capacitor cells "pcapacitor"
and parasitic-resistor cells ="presistor" in the "av_extracted" view in the Library Manager.

Which appears OK,  because "pcapacitor" and "presistor" are the default parasitic components

in the QRC "Setup" menu.  And "pcapacitor" and "presistor" are in the "analogLib".

But when I do a "q" on any parasitic cap in the "av_extracted" view,  it shows the "Model" name is "cmodel". 

And when I do a "q" on any parasitic metal-1 resistor,  it shows the "Model name" is "M1".

And when I do "q" on any poly resistors it shows the "Model name" is "PC1".  

So these model names end up in the Spectre netlist "input.scs",  which is used to run the Spectre simulation.
And the Spectre sim errors out with "SFE-23" error  ="instance is referencing an undefined model or subcircuit",

for each parasitic R and C.

Clearly the parasitic Rs and Cs are not mapping to Spectre simulate-able primitive/models.

I searched through the QRC Extraction-13.2 manual and I don't find much information about how to map
"pcapacitor" and "presistor" to simulate-able primitives like "res" and "cap" from the "analogLib".

------

It appears there are two ways to fix this problem. If there is a standard mapping file that maps "cmodel" to"cap",

and maps "M1" to "res" and "PC1"  to "res",  this would probably fix the problem.

Or, can I change something in the QRC "Setup" menu to do this component mapping ?  can I change "presistor" to "res" ?
and pcapacitor = "cap" ? or change the "Prop Id" field from "r" to "res" and "c" to "cap" ?


But I don't find a good explanation for the "Prop ID" field in the QRC manual.

Question, is this a mapping file problem, or lack of mapping file problem ?  , or a QRC "Setup" menu problem ?

And if it is a missing mapping file, what is the format of this file  ?  and how do you point to it ?


Is this a file that should have been supplied inthe QRC rules director ?

----

That's my question today.

  thanks,     -steve

  • Cancel
  • Andrew Beckett
    Andrew Beckett over 8 years ago

    Steve,

    Most likely this is because you have the settings on the Netlisting tab of QRC incorrectly set. If you have them set to "Include Model" for the two parasitic entries, it will end up adding a model parameter on each parasitic in the extracted view (which will then get netlisted by the spectre netlister, for example) which gives an indication of which type of parasitic it is. Most of the time, you probably don't want that and so should have it set as follows:

    Regards,

    Andrew

    • Cancel
    • Vote Up 0 Vote Down
    • Cancel

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.

© 2025 Cadence Design Systems, Inc. All Rights Reserved.

  • Terms of Use
  • Privacy
  • Cookie Policy
  • US Trademarks
  • Do Not Sell or Share My Personal Information