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HMusu's avatar
HMusu
Icon for New Contributor rankNew Contributor
5 years ago

Hi, For Transceiver IO's do we need to match trace length for multiple channels/lanes for 40GB Ethernet using QSFP+ connector ?

1 Reply

  • CheepinC_altera's avatar
    CheepinC_altera
    Icon for Regular Contributor rankRegular Contributor

    Hi,

    As I understand it, you have some inquries related to the trace length matching. For your information, generally for 40G Ethernet, there will be 10G x 4 bonded XCVR lanes. It is recommended for you to match the length for these lanes to ensure minimal lane-lane skew.

    Just for ddditional information, you may also refer to the device datasheet ie "Transmitter Channel-to-channel Skew Specifications" in A10 device datasheet for max TX CH-CH skew within the FPGA.

    Please let me know if there is any concern. Thank you.

    Best regards,

    Chee Pin