FEDEVEL
Platform forum

mulfycrowh , 12-15-2022, 01:34 PM

Hi everyone,

I have a 4 layer board.
I have to modify the design.
Previously I didnt have any differential pair on midlayers but now I have to add a few ones.
Adding such pairs initiates a clearance rule violation between tracks.
The rule is set to 0.15mm and the space between pairs is 0.107mm.

I could set the rule to 0.1mm but I don't understand why the rule enters into a violation since there are differential pairs and not tracks.

Thanks for any idea!

qdrives , 12-16-2022, 10:12 AM

If they are differential pairs, they should follow the differential pair routing rules, which includes a minimum gap.
Perhaps the clearance rule is bigger and should exclude the differential pairs.
If you right click on one of the tracks, select "Applicable binary rules" and then click the second track, Altium should mention which rules it applies between them.

WhoKnewKnows , 12-17-2022, 06:01 AM

Also, @robertferanec has a few videos on setting up differential pair routes. Perhaps watch and it may jog your memory on what's required to set these up, in case you've left something out