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VSR not dropping vias to short all pins

MARTH0401

I have multiple horizontal m2 layers (one on top of the other that have the same terminal and net name). The only diffrence is the pin names are different. VSR only connects only one pin at the top level after the run finishes. The expectation is that m3 would be extened from top to bottom of each horizontal m2 layer and a v2 is placed on each horizontal layer. Instead VSR only drops one v2 and call it quits. Why will VSR not connect all the pins together here?


  • This is what I am trying to explain in the description above. Why is VSR not wanting to extend M3 all the way to the top and drop via2 for the remaining three pins? a_1,a_2,a_3,a_4 all share terminal and net name "a". 

    I already tried "must connect all pins" and "must connect" features in pin connectivity settings and VSR did not do anything different. I assigned pin "a" as must connect all pins and also try must connect. Is something still preventing the VSR router from not recognizing the pins?

    I have also tried setting the following variable in the .tcl file because I need to connect more than one instance in the layout and currently the router is only connecting one single pin.
    setvar db.connect_IO_pin_shapes true

  • in reply to MARTH0401

    The model you describe should work. What does the form 'Connectivity -> Pins -> Pin Connectivity Setting' show?

  • in reply to RobMan

    It shows the following structure 

    -Ungrouped Terminals
          - a [(must connect all pins | symbolic_default | signal)]

                   - a_1

                       a_1

                   - a_2

                       a_2


    and so forth..

  • in reply to MARTH0401

    Hi,

    Any feedback on this? Its been a few days 

  • in reply to MARTH0401

    Hi,

    Apologies. I missed your update. The 'mustConnect' model looks correct. I suggest you contact customer support.

    Rob.

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