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Relative delay analysis is impacted by pbar

Does anyone know how to not include a pbar in a constraint manager analysis? I have some relative delay constraints applied on a group of differential nets. When I analyze the design these all show an error. If I delete the plating bar from the design they are all passing. The plating bar gets generated on the Substrate Geometry / Plating_Bar class. I understand that I could just delete the plating bar to verify the constraint but the issue is when I archive this design I would like it to be clean meaning it is in the final state for manufacturing AND passing all constraints according to design reviews.

Anyone have an idea?

Thank you!

0 mahimag over 1 year ago

Hi JS532, Can you share what error you are getting?
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0 JS532 over 1 year ago in reply to mahimag

Hi mahimag,

I don't get an error. What I get is values very different. When the pbar is present, the values are ~15ps. When the pbar is deleted, the values are ~5ps. The following are shown under the Name column for an example:

CLKP: die.90:bga.A1 = 0.013ns relative delay within the match group

pbar.76:bga.A1 = 0.012ns

pbar.76:die.90 = 0.015ns

Perhaps there's a way to exclude the pbar from the calculation but I haven't found it. It's located on the Substrate Geometry / Plating_Bar class so I'm not sure why it would be included in the calculation. The only way I have found that works is to delete pbar.

I would attach some images but the interface isn't allowing me.
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0 mahimag over 1 year ago in reply to JS532

Hi @JS532, in SPB 23.1, we have a property "Ignore_Length_Calc". This can be added to clines for this purpose.
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