You are reading a single comment by @Gordon and its replies.
Click here to read the full conversation.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
@Gordon
I'm not really sure what's up - I asked around and all we could think of is that the diode breaks down with a certain reverse voltage. Which revision board do you have? I did change the diode for a better one on the rev 1.4.
Now, when we checked, the reverse voltage was within the allowed limits - 30v or so, but I wonder whether if the diode has been stressed - especially on the 1v3 (even a momentary short) - then it might break down at a lower voltage than rated.
If you're ok just powering it off 12v, how about just removing that diode? It should be relatively easy to take off (or just lift one side) with a soldering iron, and should totally fix your problems - although after that you'd have to make sure the Pico was powered externally to program it.
Sorry about that, but it's about the only thing I can think of at the moment.