Stats

Locked Locked
Replies 3
Subscribers 126
Views 14125
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

QRC runs for RC and C only av_extracted views report different values of net capacitance for a net

Hello all,

To start things off I am using:

IC6.1.4

Assura 4.12.017

QRC 9.14.002

I’m trying to minimize parasitics in a circuit and I’ve encountered something weird.

Upon completing a clean LVS, I run QRC and create two av_extracted views, one with “RC” Extraction Type and the other with “C Only” Extraction Type. I call them av_extracted_RCs and av_extracted_Cs accordingly.

I'm trying to minimize parasitics in a circuit, and I’m using the Parasitics-> Report Parasitics ->Net Capacitors to view my progress. I have encountered something weird when I look at the net capacitances. There is a difference in the total net capacitance whether I load av_extracted_RC or av_extracted_C! If I load my av_extracted_Cs it reports a total net capacitance X fF for a given net x, but if I load my av_extracted_RCs it reports more net capacitance (Y) fF for the same net x.

Why does the extracted view with RCs show more net capacitance than the extracted view with only Cs? This is puzzling me and I hope someone has encountered this before. Thanks in advance.

Cheers,

Brian

Andrew Beckett over 12 years ago

Brian,
Probably best to contact customer support over this so that we can investigate. I would expect them to be different (because the net is fractured into pieces when using RC), but I can't think (off the top of my head) why they should be significantly different.
Regards,
Andrew.
Cancel
Vote Up 0 Vote Down

Cancel
bnugent over 12 years ago

Andrew,

I have contacted my local cadence support and resolved the issue.

Cheers,
Brian
Cancel
Vote Up 0 Vote Down

Cancel
Meny Lea over 11 years ago

Hi,

im having the same issue. what was the solution ?
do you have CCR number ?

thx

meny
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.