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TUSB8041A: the max cable length before the hub and after the hub

Expert 7470 points

Replies: 6

Views: 71

Part Number: TUSB8041A

Hi team,

We want to check about the max cable length before the hub and after the hub. Before the hub is FR4 pcb trace, after the hub is the PCB trace plus the usb 3.0 cable. We cannot find EQ and DE information in the datasheet. Thanks.

BTW: My customer want to use it with AMD platform, please also help check whether it's ok. Thanks.

  • max PCB trace length is 8in, max USB3 cable length is 3m.

  • In reply to Brian Zhou:

    Thanks for your answers. How about the length before the chip? Do we have some details about the internal adaptive EQ? We want to get the advantages of the spec, whether it’s only good when using the aging cable? whether it can be compatible with USB2.0 without changing anything?Thanks.

  • In reply to Frank Xiao:

    HI Frank,

    We recommend a max of 8 inches of PCB traces before or after the hub, longer PCB trace length is possible but care must be taken to match trace length and control impedance.  Max USB 2.0 cable length is 5M.



  • In reply to JMMN:

    Hi JMMM,

    The max PCB trace length 8in, max USB3 cable length  3m are before plus the after the hub? whether it has some guideline where we put the hub, or just based on the power loss, if before loss is larger, we put near the source side, otherwise we will put near the end point side, correct? So our device cannot be changed the EQ manually. Thanks.

  • In reply to Frank Xiao:

    Hi Frank,

    To clarify, the TUSB8041A can handle 8 inches of PCB trace length on the board from hub to connector.  At the connector the hub can accept USB compliant cable lengths (USB 3.0 - 3M/ USB 2.0 - 5M).

    HOST - 3M USB 3.0 cable - 8" PCB - HUB - 8" PCB - 3M USB 3.0 cable - device



  • In reply to JMMN:

    Hi JMMN,

    other team member recommends to use the TUSB8042A to replace TUSB8041. Whether the EQ and cable capability of 8042A is the same as 8041? Thanks.