Hi everyone,
I replaced the resistors with solder blobs and the board works fine. Even when booting from flash with the external PSU. All fixed.
Thank you all again for your help.
I measured the resistance of the data lines and realised that the resistors I placed were not 27 ohm, but 27k ohm. Oops!I agree it's a little unlikely that your via-in-pad has failed the same way on all your boards, but for the USB traces at least you can easily measure with an ohm-meter: the RP2040-end of USB_D+ and USB_D- is an ordinary pad, so you could measure from there round to the pin on the USB connector (or better still, to the end of a USB cable plugged in to the socket) and you should measure 27ohm or just over.
I replaced the resistors with solder blobs and the board works fine. Even when booting from flash with the external PSU. All fixed.
I should have listened!I manged to make a copy paste error in my BOM file and ended up with 10k resistors instead of 27R on the USB series resistors, on my first design. That did not work. Maybe check that yours are correct.
Thank you all again for your help.
Statistics: Posted by SportingClamshell — Sun Aug 04, 2024 2:21 pm
