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How do I prevent differential pairs from being checked for single-ended impedance in Hyperlynx DRC

Question asked by gaborsz on Sep 5, 2019
Latest reply on Sep 12, 2019 by Rory Riggs

When running rules on the entire design, the impedance checking for single-ended signals seems to understand that it should ignore net classes like power and ground (constant nets).  However it incorrectly checks differential pair nets for impedance.  For example in a design with 100 ohm diff pairs and 50 ohm single-ended signals, if I run rules on the entire design, the differential pairs may all pass with the correct differential impedance, but then fail in the single-ended impedance check since they will have significantly higher than 50 ohm single-ended impedance if they are tightly coupled.  Is there some way to automatically exclude differential pairs from the single-ended impedance rule check, or do I need to create an object list of all signals other than diff pairs?

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