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Add pins via skill to all symbols in lib

HoWei
I received an IP technology package from the foundry.
The package contains of:
- oa-lib with symbols only
- CDL/Spice netlist

Now I included the oa-lib with symbols and want to import the spice netlist into this library.
The problem is, that all the symbols do not have any supply pin - but the netlist has supply pins for each sub-circuits (e.g. VDD, VSS, VNW, VPW).
The import will fail as long this discrepancy exists.
One way to handle this discrepancy is to add the missing pins to the symbols via skill (there might be other options as well , line global nets, etc., but we would like to have additional pins for flexibility).
I would like to add a VDD pin on top and a VSS pin at the bottom of the symbol for each symbol in the library.

My questions:
1. My skill skills are rather nil, so I am asking if someone can send me a skill-code that I can use as a starter and customize to match my requirements ?

2. Can you share your experience with such IP import into Virtuoso (e.g. for standard-cells or GPIO libs) - is it the common way to do a lot of customization to the IP package ? I would expect to get symbols for the standard-cells for which you can just by the symbol tell if its an AND, NAND, INV, OR - but apparently this is not the case.
3. Is there any other option on how to import this netlist into the lib ?
Thanks
HoWei
Parents
  • HoWei

    Now I managed to create a skill script which steps thru the library cells and checks for each cell-view the corresponding .SUBCKT in the SPICE netlist for additional pins.

    If the cell requires additional pins on the symbols,I create them instantly at the proper coordinates (the coordinates are calculated realitve to the boundary box of the symbol).

    Thats working fine and I did not expect to get this managed so quickly.

    BUT, after I modified the symbols and I do

    dbSave(cvId)

    dbClose(cvId)

    The previous existing pins and shapes are deleted and only my additional pins are saved in the symbol.

    If I do not "dbSave() dbClose()", then the cellview has all previous shapes and pins and in addition my newly generated pins.

    Why is that ?

    How can I save the symbol-view will all shapes ?

  • RK56
    in reply to HoWei

    Based on your description I guess you are opening the cellview in write mode instead of append mode

    -Ramakrishnan

  • HoWei
    in reply to RK56

    Yes, you are right.

    I was trying both options "a" (append") and "w" (write) when opening the file and it happened that this is the behaviour when I do "w" for opening.

Reply
  • HoWei
    in reply to RK56

    Yes, you are right.

    I was trying both options "a" (append") and "w" (write) when opening the file and it happened that this is the behaviour when I do "w" for opening.

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