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Relative prop delay by layer

Simple

 I have a MG Relative Prop Delays that are  changing layers 2-3 times.  The engineer whats to not only have the Relative Prop Delay for the group for the overall length but rule that will put a Relative Prop delay for each layer.  The idea being that all traces stay on a certain layer for the same distance.  The second requirement is a via count and usage to remain the same with in the MG.  Currently on the board I am using 4 different Micro vias, 3 Blind vias and 1 through via, the engineer would like for me to make a rule that will look within a Match Group and make sure the via count and via usage is the same with in the group.  Normally  would just do this by hand, but on this board I will have close to 500 of the match groups....

I was thinking this is the perfect use for the formulas for the Relative Propagation Delay per layer and the the vias...maybe the same??  help.

  • jch teyssier

    In XL licence level and higer, you can activate "Z propagation delay". It will take in count the thickness between two layers when passing thru via or component thru pin.

     

    Jean-Charles 

  • Simple

     That is only 1/2 the issue.  The SI engineer is more worried about the LCR and stub lenght of the via.  The Z-delay will only measure the distance to the layer and not take into account the stub (if there is one).

  • Ejlersen

    Hi

    You can define layer sets that will try to make sure that the nets are only routed on certain layers. This is done in the Wiring section. During routing the net will then have a preference for these layers and you could then limit the number of vias used.

     

    Best regards

    Ole

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