TUSB2077A port usage

Hello Anoop,

1. Yes it is possible.

2. If you configured all your downstream ports in the same way, there should be no reason to only two ports are failing, unless the hub detects an overcurrent condition.  Could confirm that all your USB devices are been enumerated when you connect them directly to the USB host?. Please share your schematic to provide a quick support.

Regards.

Hi Joel,

Thanks for your information.

Now am able to communicate with the ports. I have changed the RC section 27R to 22R. Is this make any sense?

I have another question, two of my ports are unused,, but one of this port is showing as unknown device, any reasons?

2728.TUSB.pdf

If any pulldown is no longer in place then it may be possible for the corresponding input to rise suggesting a LS or FS device is connected. Similarly if a 27/22R resistor is not making contact with it's PCB pads, or you damaged tracks/pads when replacing the resistors.

Of course if you probe the point, it will of course be pulled low via the probe.

Hi Anoop,

The DP and DM signals of the unused port should be tied to ground with 15K resistors like the pull-downs used on the active ports.

Regards

Hi Joel,

I have Pull downed the un used ports using 15K and pull up enabled on OVRCUR pins of active ports. But some times on my windows it shows as unused ports.

6303.TUSBHub.pdf

Please take a look on my schematic and suggest me if am doing correct?

Hello Anoop,

Your schematics look correct. Could you post a picture of the message that is shown on Windows?

Regards.