2019-08-21 03:53 AM
After a redesign of the PCB, STM32F401RB is not recognized by the PC when connected via USB.
There is no change on the USB Connections. There are 22R resistors connected in series with the USB data lines.
Is this issue related to the value of the resistors?
The thickness of the PCB has changed but there is no microstrip lines that would change the line impedance.
Please check the schematic attached.