Oh, it's getting interesting. ![:)]( "Smile")
I bet that there are multiple factors combined, not just a single cause.
It could be something wrong with inductors, something like being weakened (can short between windings if stressed enough).
I suspect also the buck converter from Waveshare board.
That one has no overvoltage spike control, combined with a low capacitor, just doesn't look good ... actually looks like that bad behaving power source I've tested, or look here:
MP1584 https://electronics.stackexchange.com/q ... -converter
You can see a note which ... just looks ugly:
I bet that there are multiple factors combined, not just a single cause.
It could be something wrong with inductors, something like being weakened (can short between windings if stressed enough).
I suspect also the buck converter from Waveshare board.
That one has no overvoltage spike control, combined with a low capacitor, just doesn't look good ... actually looks like that bad behaving power source I've tested, or look here:
MP1584 https://electronics.stackexchange.com/q ... -converter
You can see a note which ... just looks ugly:
At no load or light load, the converter may operate in pulse skipping mode in order to maintain the output voltage in regulation. Thus there is less time to refresh the BS voltage. In order to have enough gate voltage under such operating conditions, the difference of VIN –VOUT should be greater than 3V. For example, if the VOUT is set to 3.3V, the VIN needs to be higher than 3.3V+3V=6.3V to maintain enough BS voltage at no load or light load. To meet this requirement, EN pin can be used to program the input UVLO voltage to Vout+3V.
Statistics: Posted by gmx — Fri Nov 15, 2024 1:09 pm