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Innovus does not route net with non-default rule correctly

FormerMember
FormerMember

Dear Community

I use the following code in Innovus 21.10 to route a net called "VSE2" that is supposed to be much much wider than the remaining nets

add_via_definition -via_rule via1Array -row_col {3 3} -name via1_3x3
add_via_definition -via_rule via2Array -row_col {3 3} -name via2_3x3
add_via_definition -via_rule via3Array -row_col {3 3} -name via3_3x3
add_via_definition -via_rule via4Array -row_col {3 3} -name via4_3x3
add_ndr -name 1_46w1s -width {MET1 1.46 MET2 1.46 MET3 1.46 MET4 1.46 MET5 1.46 METTP 1.46} -via {via1_3x3 via2_3x3 via3_3x3 via4_3x3} -generate_via
setAttribute -net VSE2 -top_preferred_routing_layer 3 -bottom_preferred_routing_layer 2 -preferred_routing_layer_effort high -non_default_rule 1_46w1s
setNanoRouteMode -routeSelectedNetOnly true -drouteUseMultiCutViaEffort high
selectNet VSE2
routeDesign

This is the output:

Why is the right-hand side not routed correctly? What prevents Innovus from routing the net according to the NDR?

Thank you for any suggestions.

  • Hi Domi,

    Apparently, NDR is soft rule and tool might have seen few benefit in not honouring it.  In order to guide tool to honor NDR strictly, please add the following,
    setNanoRouteMode -routeSelectedNetOnly true -drouteUseMultiCutViaEffort high -routeStrictlyHonorNonDefaultRule true

    --
    Ramesh

  • FormerMember
    FormerMember in reply to RamesNaikBhukya

    Dear Ramesh

    Thank you very much for your response. Unfortunately, using -routeStrictlyHonorNonDefaultRule true does not alter the result. I also tried -routeStrictlyHonorNonDefaultRule 1:4 but the result was the same: wrong vias and the NDR was not honored completely. I scanned the log file for potential problems but I could not find any message or warning that would indicate a problem.

    A quick side note for everyone else reading this: Using -generate_via is actually wrong in this context. It generates new vias based on existing ones, which is not what I want. Omitting this argument yields the correct behaviour in this case.

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