5mA or so is probably in fact right at this stage of booting - I'm used to about 1-2 mA while held in reset, 10mA when running, but if it's sitting there in the bootrom not having yet loaded any code from flash (because there isn't any) then the clocks are slower and 5mA sounds reasonable.
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.
After that, you can try it powered up and look at the voltages on USB_D+/D-.
Operating as a device, the RP2040 should present a pull-up resistor on D+ to indicate that it's a full-speed device. Hubs (including PC ports) should have week pull-down resistors on both D+ and D-. So with the RP2040 powered and nothing plugged in to the USB, you should see D+ high and D- low. Plug in a PC and the voltage should dip very slightly, and then things should start happening as the PC queries the RP2040 for tis device descriptors etc.
I'd also be wanting to get something onto the RP2040's reset (RUN) pin. You haven't wired this to anything on your board so it will be tricky to solder to, but maybe you can poke some sort of probe or piece of stiff wire (other end connected to GND) in there by hand - taking care not to short the 1.1V supply on the capacitor nearby.
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.
After that, you can try it powered up and look at the voltages on USB_D+/D-.
Operating as a device, the RP2040 should present a pull-up resistor on D+ to indicate that it's a full-speed device. Hubs (including PC ports) should have week pull-down resistors on both D+ and D-. So with the RP2040 powered and nothing plugged in to the USB, you should see D+ high and D- low. Plug in a PC and the voltage should dip very slightly, and then things should start happening as the PC queries the RP2040 for tis device descriptors etc.
I'd also be wanting to get something onto the RP2040's reset (RUN) pin. You haven't wired this to anything on your board so it will be tricky to solder to, but maybe you can poke some sort of probe or piece of stiff wire (other end connected to GND) in there by hand - taking care not to short the 1.1V supply on the capacitor nearby.
Statistics: Posted by arg001 — Thu Aug 01, 2024 8:26 pm