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Original question:

DS160PR410: request to share datasheet of DS160PT801.

DS160PR410: Trace ristriction

Jeff Xie
Intellectual 1780 points
Part Number: DS160PR410

Hi team,

Customer currently have PCIe traces that are connected across two boards, and in the middle is TI’s Redriver chips, 


1) Customer's PCIe trace is relatively long, and the single board has exceeded 12000Mil. can they use two Redrivers to enhance the drive? Do any customers use it like this?

(2) They want to know the official PCIe PCB trace length limit. Can you provide us with this?

  • 0
    TI__Genius 10760 points

    Hi Jeff,

    A board (Using FR-4 material) with a trace length of 12000mils will have ~-15.6dB of channel loss @8GHz.

    The DS160PR410 can equalize channel losses up to ~17.8dB @8GHz.

    Assuming the 2nd board has equal or less channel loss than the first, one re-driver should be adequate.

    The PCI Express specification defines the maximum channel loss as opposed to maximum trace length.  The maximum defined channel loss for PCIe Gen 4 is -28dB.

    Using one re-driver in the middle of the two boards will leave about 1/2 of the allowable channel loss budget.

    It is possible to use two re-drivers but not likely required in this case.