What is the purpose of curved PCB traces?

Question

I have seen traces like this enough times to begin wondering if there is a purpose and benefit. The only technical explanation I can come up with is that perhaps these curved traces increase the inductance between the end-points (for the type shown on the right of the IC) and decreases capacitive coupling for the type shown at the bottom. If this is the case, why would that be desirable? If not, what is the purpose? Also, I thought it was generally back practice to include sharp edges in the traces.

enter image description here

This particular screencapture is taken from the PCB of the new Raspberry Pi 2 B

@PlasmaHH, Thanks. I did a search but did not try describing this behavior as "wave"-like. — sherrellbc, Feb 04 '15 at 15:51
Never use the onsite search, always use google: https://www.google.com/search?num=50&newwindow=1&q=curved+PCB+traces+site%3Astackexchange.com — PlasmaHH, Feb 04 '15 at 15:53
Oh and btw. there is even a tag serpentine-trace for it on this site ;) — PlasmaHH, Feb 04 '15 at 16:03

score 3 · Answer 1 · answered Feb 04 '15 at 16:00

3

The curved ones on top are for delay. At high frequencies, sometimes, you need the signals achieving one point at right times. So you can retard a signal raising the length of the trace.

answered Feb 04 '15 at 16:00

Pedro Quadros

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What is the purpose of curved PCB traces?

1 Answers1