TUSB7320 PCIe differential pairs nagative and positive signals reverse.


I'm routing PCB with TUSB7320. I need know - is it possible to change polarity between P and N signal of differential pairs on PCIe interface? On USB3.0 interface here is written in datasheet of TUSB7320 what it is possible to change. But about PCIe I found only in "TUSB73x0 Board Design and Layout Guidelines.pdf" on page 25: "It is permissible to swap the plus and minus on either or both of the PCIe differential pairs. This may be necessary to prevent the differential traces from crossing over one another. ..." 

Is it true? If it's true, how can I configure pin reverse in registers of TUSB7320?

Thank you!


1 Reply

  • Hello,

    yes, you can swap the plus and minus polarity of the differential pair, there is nothing to change on the internal registers, the PCIe interface automatically handles the polarity swap.