FEDEVEL
Platform forum

mulfycrowh , 12-02-2022, 05:38 AM

Hi everyone,

I am having a problem to route differential pairs because they are swapped.
The IC I am using doesn't allow any swapping.

I thought about a solution using 2 jumpers (or better capacitors because I have capacitors on my design), but the problem is that such component doesn't exist.
The jumper could have a package of XX01.
The length should be about 2mm.

Did you already use such solution?

Paul van Avesaath , 12-03-2022, 12:39 PM

only option really is to have a second layer that would be the best...
if that is not possible the only option i can think of is doing it manually after production with some wires (placing a 0402 inline) then cross some wires on the board.. should be ok.. (depending on the speed of the diffpair)
but if i could see the source and destination of you signal i can say more .. usually there are some tricks you can do. but based on your picture i cannot say if it is possible.

robertferanec , 12-05-2022, 04:06 AM

The best is to have two layers to swap diff signals. On 1 layer, only the option is to try to rotate components somehow, use different components with different pinout or go behind the pins and then come back from the other side (as you did on the picture). I am not aware of any components which could be used to swap diff pairs.

Paul van Avesaath , 12-05-2022, 07:55 AM

thinking of it, you could so something like this
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