Got a hilt on the bench with a regular blue LED (same as a normal dome LED but tiny smd version). Wired to SD+ pad (3.3 volt pad was already busy) and PowerPin 1 with a simple blinking blade style.
It was working fine, but now bizarrely stays on solidly until I use the kill key.
Just wondering if this indicates FET fafailure as I can’t think what else would be leaving it powered all the time when the code should - and indeed was for a while - be telling it to blink.
Not a huge drama as I can rewire to another pad that feeds another regular LED and have them both do the same thing (I’d set them to blink alternately). But I would like to understand what’s happened, as I haven’t had a FET fail before (at least not without me having made some wiring mistake and blown it).
Yeh but might have to fudge something to get probes small enough to contact separate FET solder legs. What am I measuring for, beyond volts between 3.3/SD pads and power pad?
nah just probe batt(+) and the LED pad and watch voltage when the LED should be on, off, blinking etc.
If it never changes, then yeah, it would seem the FET is stuck open or partially open. Not blown, like exploded)
Oh, and I should add, I suspect the meter will confirm exactly that (it’s late here as I write this, so not heading out to the workshop just now). But the LED was still lit after the Idle Off Time had kicked in and everything else was powered down.
It’s a busy build, but I can share one - it just means two LEDs (red 3mm and blue smd) will blink together instead of alternately. But there’s so much else going on I don’t think it will matter much! LOL!
