Electronic – USB multiplexer – swap pins

pcbusb

I want to use the USB 2.0 multiplexer TI TS3USB221ARSER. But on the PCB the D+ and D- pins of one connection are crossed (see attached image). USB pins crossed

Is it okay to change the D+ and D- pins on all sides of the multiplexer to fix this? The two alternatives are:

  • use a via on one signal trace to switch to the other side (I always read one should avoid vias in high speed connections?)

  • avoid this problem with long connections (see second attached image. Trace lengths/trace impedance not calculated in the image).
    USB solution2

Which is the best solution?

Thanks!

Best Answer

The only way I can see this being a problem is if this switch waits for the end of a USB frame to perform the switch -- although signaling is differential, end-of-frame and start-of-frame events are denoted with DC levels (e.g. D- high and D+ low).

But I doubt this is the case and it's probably fine to swap.

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