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Calibre LVS errors for a design generated in Encounter

oAwad

Hello all,

 I made a design in SoC Encounter using NangateOpenCellLibrary 45nm. The layout had zero geometry and connectivity violations. I then needed to go to Calibre for LVS and PEX in order to do post-layout simulations, so I did the following in Encounter:

1) Design > Save > GDS/OASIS, then I provided the map file and merged library gds file that came with PDK "NangateOpenCellLibrary.gds" and didn't select "Uniquify cell names"....then finally hit Ok.

2)Design > Save > Netlist,  and I selected the two options in the window and hit Ok.

Then for Calibre part:

1) I run "v2lvs" command to generate spice netlist for LVS

2) I then run LVS using Calibre -gui

In LVS transcript window, I get tons of these two warnings: 

 Open circuit - Same name on different nets:

 Top level port name "KEXP0/n2089" at location (3.515,165.69) on net 2 not valid for netlisting; net id used instead.

(I think the above warning is the reason of the errors)

and in the LVS report I get these:

Error: Different numbers of ports (see below).
Error: Different numbers of nets (see below).
Error: Different numbers of instances (see below).
Error: Connectivity errors.
Error: Property errors.
Warning: Unbalanced smashed mosfets were matched.
Warning: Ambiguity points were found and resolved arbitrarily.
Warning: LVS property resolution maximum exceeded.


NUMBERS OF OBJECTS AFTER TRANSFORMATION
---------------------------------------

Layout   Source    Component Type

------       ------      -------------

Ports: 12065       35        *

Nets:  29877   29720      *

Instances: 1265 1261      * MN (4 pins)
                  790 790         MP (4 pins)
                  5781   0          * _invb (6 pins)
                 10551 16326   * _invv (4 pins)

(If you added instance "_invb" and "_invv" in both layout and source, they have the same total)

I don't have experience to debug these errors, so can anyone tell me how to debug them ? 

 

Parents
  • No it was not intended. But, how on earth I have open circuit and the layout has no geometry and connectivity violations in Encounter ? Moreover, do I need to re-run the whole flow again or there is an easier way to fix it ?

    If there is an easier way than re-running the flow, please tell some hints on how to debug these issues as I don't have much experience.

    Thanks
Reply
  • No it was not intended. But, how on earth I have open circuit and the layout has no geometry and connectivity violations in Encounter ? Moreover, do I need to re-run the whole flow again or there is an easier way to fix it ?

    If there is an easier way than re-running the flow, please tell some hints on how to debug these issues as I don't have much experience.

    Thanks
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