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Special open on VCC, and GND while doing connectivity check after using SRoute command

Hi all,

After doing sroute for pad pins only, the connectivity report gives the following violations:

Net VCC, Pin VDD_PAD.VCC: unconnected terminal at (696.070000,1633.320000) (732.870000,1636.800000)
Net VCC: special open at (265.350000,265.350000) (1371.450000,1423.350000)
Net GND, Pin VSS_PAD.GND: unconnected terminal at (696.070000,0.000000) (732.870000,3.480000)
Net GND: special open at (273.960000,213.250000) (1362.840000,1361.240000)

Where: VDD_PAD: is the VDD pad, and the pin VCC is the only pin defined for it in the lef. The same for VSS_PAD.

My lef power, ground pins either for standard cells or core power pads is VCC, and GND, and also I defined my global nets in encounter to be the same names.

I used those commands for global connect:

globalNetConnect VCC -type pgpin -pin VCC -inst *
globalNetConnect VCC -type net -net VCC
globalNetConnect VCC -type tiehi
globalNetConnect GND -type pgpin -pin GND -inst *
globalNetConnect GND -type net -net GND
globalNetConnect GND -type tielo

My thoughts tell me that I can ignore the unconnected terminals warnings, because it will be connected using i/o filler cells to complete the power ring for pads.

Attached is a pic. for my chip with violation markers.

Any help how can I solve this !

Thanks you.

AbdUllah,

Kari over 8 years ago

without having the design in my hands, it sounds like your theory is right. add the IO filler cells, rerun verifyConnectivity, and see if you still get the warnings.
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