• Resolved

TUSB2077A: No USB Device Descriptor(Code 43) or Crystal output on power up

Prodigy 130 points

Replies: 2

Views: 33

Part Number: TUSB2077A

Dear E2E,

I'm have a PCB with TUSB2077A  I am getting a no USB device descriptor error when i plug into windows. I get power successfully both 5V & 3.3V but there is no crystal.

I have verified that the device is not in suspend mode ( suspend = high 3.3V). The crystal is stuck at 1.5V and there is never any 6MHz crystal oscillation. I have used the same crystal part on other TI hubs and it works so I don't think it's an issue with the crystal.

I have tried modified the Power On Reset circuit and have verified with the scope a timing of 600 uS between 90 % of 3.3V( 2.97V) and Reset no longer asserted. I have also tried other resistors instead of 15K an 0.1uF but nothing has changed.

Can you please review my schematic and let me know if you notice anything ? I'm happy to try any change or collect scope captures to further investigate.