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PAD connections in Encounter

naderi

 Hello everyone, 

I have manually modified synthesized RTL to include pad cells and their connections, then, fed them to Encounter v6.2 for place and route. After place and route, I realized vdd and gnd net are not connected to any pin.

I am wondering if I have to remove pad cells from input RTL.

Also, other IOs are connected to the associated pads by a metal layer that has the minimum width. What is the best way to define width of metal layer for connecting to the pads.

Thanks,

Ali 

Parents

  • Hi Bob,

     

    I repeated the flow and used the "globalNetConnect" command, and still getting the same results.I think the problem of vdd/gnd connection is due to pad cells in the CMOS library from STMicro. The power pad cells have only one pin called "DUMMY". It seems the Encounter does not recognize it as a pgpin. I get following warning during "placeDesign" when I have connected "DUMMY" pin to gnd using a wire.

    **WARN: (SOCDC-348):    The output pin ioco_vssioco_1/DUMMY is connected to power/ground net gnd. This can compromise the delay calculation. Fix the netlist and re-run. 

    After SRoute the vdd/gnd warnings are following:

    Begin power routing ...
    **WARN: (SOCSR-1256):   Net vdd does not have pad pins to be routed. Please check net list or port class. (must be CORE class).
    **WARN: (SOCSR-1256):   Net gnd does not have pad pins to be routed. Please check net list or port class. (must be CORE class).
     

     

    About the second problem (width of the wire when connecting to a pad),as you mentioned, the option [-padPinWidth real] for sroute could solve the problem.

    Thanks,

    Ali 

Reply

  • Hi Bob,

     

    I repeated the flow and used the "globalNetConnect" command, and still getting the same results.I think the problem of vdd/gnd connection is due to pad cells in the CMOS library from STMicro. The power pad cells have only one pin called "DUMMY". It seems the Encounter does not recognize it as a pgpin. I get following warning during "placeDesign" when I have connected "DUMMY" pin to gnd using a wire.

    **WARN: (SOCDC-348):    The output pin ioco_vssioco_1/DUMMY is connected to power/ground net gnd. This can compromise the delay calculation. Fix the netlist and re-run. 

    After SRoute the vdd/gnd warnings are following:

    Begin power routing ...
    **WARN: (SOCSR-1256):   Net vdd does not have pad pins to be routed. Please check net list or port class. (must be CORE class).
    **WARN: (SOCSR-1256):   Net gnd does not have pad pins to be routed. Please check net list or port class. (must be CORE class).
     

     

    About the second problem (width of the wire when connecting to a pad),as you mentioned, the option [-padPinWidth real] for sroute could solve the problem.

    Thanks,

    Ali 

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