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HasanTheSyrian_ , 09-27-2025, 01:38 PM

Should I length match Ethernet diff pairs to each other? I have already matched the diff pairs to themselves

HasanTheSyrian_ , 09-27-2025, 01:40 PM

QDrives , 09-27-2025, 02:16 PM

Is that 8mm or 8mil difference? For 8 mm I would match them more.

HasanTheSyrian_ , 09-27-2025, 02:17 PM

about 8mm max between pairs

HasanTheSyrian_ , 09-27-2025, 02:17 PM

also look at the pinout :( the pairs overlap

QDrives , 09-27-2025, 02:22 PM

*Overlap*? Do you mean that they short as you put them on the same layer?

HasanTheSyrian_ , 09-27-2025, 02:52 PM

theyre not on the same layer lol..

tomas.kaplan , 09-29-2025, 08:08 AM

If there is ground between the pairs which "overlap", its fine. If you have polygon cutout under pairs, i would not route it above each other. I would recommend using different collors for different layers tho 🧐 . From my experience, if I had space around my pairs, i matched them within 100mills (2.54mm) and it worked well - 1Gb ethernet, but its generally not so critical since the ethernet cable itself have various lengths of pairs. Internet says that skew between pairs can be up to 400ps, that means about 50-60mm length mismatch between pairs. You are very safe and within the limits.