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TUSB213: How to improve the quality of USB communication at a distance of 4.5 meters?

Shawn_Wang
Expert 3811 points
Part Number: TUSB213
Other Parts Discussed in Thread: TUSB4020BI, TUSB217

Hi team

Can you recommend devices to improve the quality of USB 2.0 communication at a distance of 4.5 meters?

My customer met a problem that is when using a 4- or 4.5-meter USB shielded cable between two devices, only a few boards can correctly identify the device.

If changed 4- or 4.5-meter USB shielded cable to 2-meter USB shielded cable, all boards can successfully identify the device.

In order to achieve a communication distance of 4.5 meters, maybe a USB Hub or USB signal conditioner is a good choice.

My question is 

  1. Can a USB signal conditioner (like TUSB213) address this issue?
  2. If the answer to question 1 is YES, how to understand the description in datasheet "supports up to 5m pre-channel or 2m post-channel Cable Length"? Does it mean that if place the signal conditioner (labeled as C in the following figure) near the B board (the distance is less than 2 meters), the distance from A board to signal conditioner can support up to 5 meters? If so, it seems that TUSB213 can meet the distance requirement.
  3. The USB hub can definitely solve this problem, right? Is TUSB4020BI a good choice?

Maybe I am asking some silly questions because I am not familiar with USB devices. Thanks for your patience.

Shawn Wang

shawn-wang@ti.com

  • 0
    TI__Guru 64326 points

    Hi Shawn,

    1. This is correct TUSB213 or TUSB217 would work in this application. I recommend TUSB217 as it is our lastest USB 2 redriver. 

    2. You figure is correct, the re-driver should be placed as close to the connector as possible. Please review the FAQ linked below as the information still applies. 

    https://e2e.ti.com/support/interface/f/138/t/719929?tisearch=e2e-sitesearch&keymatch=faq%3Atrue 

    3.  I recommend using our USB redrivers however using a USB Hub could work as well although is a large, more power hungry solution.

  • 0 in reply to Malik Barton57
    TI__Expert 3811 points

    Hi Malik

    Thanks for your prompt reply.

    "the re-driver should be placed as close to the connector as possible", so the 4+1 is recommended compared to the 3+2 cable length configuration?

    Thanks for your patience.

    Shawn Wang

  • 0 in reply to Shawn_Wang
    TI__Guru 64326 points

    Hi Shawn,

    This is correct 4+1m is recommended if he redriver can be placed on a separate board. However in most applications the redriver will be place on board A and should be placed close to the connector. 

  • 0 in reply to Malik Barton57
    TI__Expert 3811 points

    Hi Malik

    Thanks for your reply.

    • "This is correct 4+1m is recommended if the re-driver can be placed on a separate board."

    Yes, the customer will use the EVM to see if the issue can be solved first.

    • "However in most applications the redriver will be place on board A and should be placed close to the connector. "

    Do you mean the connection shown below is recommended?

    If so, the maximum cable length between two connectors is only limited to 2 meters according to the description in the datasheet? 

    Thank you.

  • 0 in reply to Shawn_Wang
    TI__Guru 64326 points

    Hi,

    Your diagram is correct. Since USB is a plug and play interface, in most applications you do not have control of the design of the USB device thus we recommend putting the USB 2 redriver close to the connector on "A-USB Host". 

    The maximum post-channel in this application will most likely be longer than 2m. This is because the pre-channel is much less than 5m.