Hello, I have designed my own board based on NRF52840-CKAA-R, which uses USB power supply. The working voltage of NRF52840 is 3.3V, and my test voltage is normal
But NRF52840 doesn't have a clock, including 32.768K and 32MHz clocks. I don't know why, but I followed the schematic and PCB design of nrf52840_ckaa_config6upcb in the datasheet. However, I can't find any reason why the board doesn't have a clock after being powered on, and it can't be connected or burned through JLINK
I am using a chip, which should be set to factory settings internally. I did not connect successfully. Can you help me check where the problem lies
