I made a board from ESP32C6 (QFN40). Schematics are attached. When I go to plug it into the USB. It keeps connecting and disconnecting back to back. I checked the 3.3V rail with an oscilloscope and It is stable throughout the connection and disconnect. I can get the connect/disconnect to stop by putting the chip into boot mode. Then the device manager on windows says that device descriptor failed. Do you see any obvious issues with the schematic? If the schematic is okay could it be related to bad routing of the USB traces on the PCB? Thank you
QFN40 
\$\begingroup\$ \$\endgroup\$
2 
- \$\begingroup\$ shouldn't you he investigating what Windows tells you before looking at schematics? \$\endgroup\$jsotola– jsotola2025-04-07 18:16:49 +00:00Commented Apr 7 at 18:16
- \$\begingroup\$ Well considering I don't see such thing when I plug in a Dev board, I'd think the issue is with the design I made. \$\endgroup\$kefecik– kefecik2025-04-07 20:12:43 +00:00Commented Apr 7 at 20:12
Add a comment |
1 Answer
\$\begingroup\$ \$\endgroup\$
Here are physical things to check
- Remove tvs diodes and try again
- Check eye diagram with a scope
- Make sure layout is good with the right transmission line characteristics for usb Although if you have a short run under 5cm it's probably good.
If these aren't fixing the problem, then it could be the ESP32 (replace) or windows.
