User Tools
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General Cadence FAQs
Q. Why do we use Cadence and not any other software?
A. Detailed answer is posted here.
Q. My schematic and/or layout is locked up and I can't edit it. What should I do?
A. In short, use clsAdminTool directly from command terminal. To remove ALL the edit locks in your directory tree, type
clsAdminTool -are .
A detailed answer is posted here
Q. What should I do when prompted for license checkout when using Cadence tools?
A. Select the 'Always' option. A common rule when using Cadence is 'Never click Never.
Q. What is a PDK?
A. PDK stands for Process Development Kit. Every chip fabrication (fab) service provides a kit that facilitates design, simulation and verification of chips designed using their technology. The PDK consists of Spectre and corner models, Calibre/Diva extraction data, DRC rules, programmable cells (PCells) and miscellaneous scripts.
Q. Can I purchase and install Cadence on my personal computer?
A. No, you can only access it through an X-server client such as X2Go.
Virtuoso Schematic Editor FAQs
Q. I can't open the schematics due to the licence checkout error.
A. This issue arises when you click 'Never' when prompted for license checkout. A common rule when working with Cadence is 'Never click Never'. This option gets saved in a .cdsenv file in your home directory. To fix this issue, delete the .cdsenv file in your home directory (NOT in the local work directory).
Q. How do I convert Cadence Virtuoso Layout to an image file?
A. Link.
Virtuoso Layout Editor FAQs
Q. How do I get rid of layout grid errors when I perform DRC on my layout?
A. Make sure your major and Minor spacings in layout are multiple of the grid lambda. Lets say for 0.5u process the lambda=0.3u, then you change change the minor spacings to 0.9 and major to 4.5. The grid snap spacing can be 0.15.
Q. LVS for my extracted layout doesn't work, and shows error in si.log “Diva cannot fine switch master cell …. for instance from viewlist.”
A. Make sure that in your .bashrc the netlisting mode is set to Analog. You should have the following line in your .bashrc in your home directory. Also, note that these variables are case sensitive.
# Add this line, otherwise LVS will not work export CDS_Netlisting_Mode="Analog"
