• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 32 subscribers
  • Views 133 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TUSB4020BI: Indication of USB Device Connection

David Lin
Prodigy 30 points
Part Number: TUSB4020BI

Hi Tech Support:

We areusing TUSB4020BI in our application. In our design, we don't get VBUS from the host, so we have VBUS always connected to a 5V source through the appropriate resistor divider per the data sheet. 

When a host is connected to this USB hub, are there any bits in the SMBUS registers, or signal pins on the device, that change states as a result of detecting a host connected with USB activity? This would be independent of VBUS, which is always connected to a 5V source.

Your feedback would be appreciated.

David

  • 0
    TI__Guru**** 156171 points

    David

    The USB_VBUS is a detection input to the hub that lets the hub know when an active host is connected.  If USB_VBUS is low, the hub will not connect, but if USB_VBUS is tied high in the system when the host is not present it can lead the interoperability issues where the host and the hub get out of sync.

    Thanks

    David