• 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. import physical verilog netlist in Virtuoso

Stats

  • Locked Locked
  • Replies 5
  • Subscribers 125
  • Views 24020
  • 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

import physical verilog netlist in Virtuoso

oAwad
oAwad over 8 years ago

I generated a physical verliog netlist for my design in Encounter using "saveNetlist design.v -phys -includePowerGround -includePhysicalInst". Here is the explanation of every attribute in this command:

-phys: Writes out physical cell instances, and inserts power and ground nets in the netlist. This is used for LVS and for designs with multiple supply voltages.

-includePowerGround:    Includes power and ground connections in the netlist file.

-includePhysicalInst:   Includes physical instances, such as fillers.

WhenI try to import this netlist in Virtuoso, I get these warnings for all std cells:


WARNING (VERILOGIN-111): Cannot connect the terminal VDD in symbol AOI211_X1 as it does not have a pin.
WARNING (VERILOGIN-111): Cannot connect the terminal VSS in symbol AOI211_X1 as it does not have a pin.
WARNING (VERILOGIN-551): Number of pins on symbol DFF_X2 in library NangateOpenCellLibrary differ from the number of ports in
the HDL module description.

When I open the symbol of DFF_X2, there is no VDD and VSS symbol, so should I update the symbol of all std cells manually to have the VDD and VSS symbols ?

(I can find "VDD!" and "VSS!" pins in DFF_X2 schematic but not in its symbol)

Additionally, I get these warnings for FILLER cells:

WARNING (VERILOGIN-72): Could not find the symbol master for the instance FILLER_5. Therefore the functional
view will not have this instance.

And again there is no symbol view for FILLER cells in the std cell library.

Since, all std cells schematics have VDD! and VSS! pins but their symbols don't, was this made so that Virtuoso power these pins virtually without an explicit power source and ground ? or this is wrong and I have to update all symbols manually ?

Finally, power and ground are called "VDD" and "VSS" respectively in my verilog netlist, however they are written as "VDD!" and "VSS!" in all std cells schematics. So what is the difference between "VDD" and "VDD!" ?

Thanks

  • Cancel
Parents
  • Andrew Beckett
    Andrew Beckett over 8 years ago

    Do you need to change anything? There's generally no need to have power in the verilog if there's only one set of supplies. The supply connections are defined as globals within the standard cells; there's no need for them to be mentioned in the Verilog in that case (in general digital designers are concerned about the signal flow, not the supplies). 

    The symbols don't have supplies on them in the library, so nothing needs to be connected up.

    It's unclear to me if anything isn't working for you if you import the Verilog which doesn't contain power/ground information. I'd expect that to work... if it doesn't, you'd need to explain what doesn't work.

    Andrew.

    • Cancel
    • Vote Up 0 Vote Down
    • Cancel
Reply
  • Andrew Beckett
    Andrew Beckett over 8 years ago

    Do you need to change anything? There's generally no need to have power in the verilog if there's only one set of supplies. The supply connections are defined as globals within the standard cells; there's no need for them to be mentioned in the Verilog in that case (in general digital designers are concerned about the signal flow, not the supplies). 

    The symbols don't have supplies on them in the library, so nothing needs to be connected up.

    It's unclear to me if anything isn't working for you if you import the Verilog which doesn't contain power/ground information. I'd expect that to work... if it doesn't, you'd need to explain what doesn't work.

    Andrew.

    • Cancel
    • Vote Up 0 Vote Down
    • Cancel
Children
No Data

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