Odroid-U3 USB Failure

USB Hub - Upstream power bad

USB Hub – Upstream power bad

My Odroid-U3 is normally directly connected to one of my high power USB hubs which is used by some Block Erupters. On Friday all of the Block Erupter lights went green, I lost contact to the Odroid-U3 via the network and the power lights on the hub showed a lack of power on the upstream data port and the only things displayed on the Odroid-U3 when running lsusb via the serial console was the two USB root hub lines.

From a quick search I found this was a known issue which has been “fixed” on the boards they’re shipping currently.

Odroid-U3 AP2411 removed

Odroid-U3 AP2411 Removed

Odroid-U3 Repair

Odroid-U3 Repair

I went for the option of removing the AP2411.

 

 

 

I also soldered a piece of (ridged) tinned wire between the USB ports VBUS and the power sockets tip pad which bypasses the task performed by the AP2411.

 

 

 

 

 

Connecting it all back up the USB hub now shows the upstream port is providing power and the devices are picked up again, networking works and all looks to be back to normal.

USB Hub - Upstream power ok

USB Hub – Upstream power OK

On the forum the reason given for the failure is back powering from the device connected to the Odroid-U3 but in my case the hub is powered by a high current power supply which is not connected to the upstream VBUS (only the grounds are connected) and in the mode the hub is being used in VBUS from the upstream (Odroid-U3) is only connected to a PTC (Polyfuse) and then to the LED via a current limiting resistor to ground so no voltage is present to be back fed into the upstream VBUS. The only other thing I noticed when removing the AP2411 was R49 was missing, from the schematic I could see it was the pullup for the AP2411 EN pin to enable the output – not sure if that’s relevant to the issue…

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