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verify no connector pins look soldered together
verify no pins on STM32 look shorted
verify all components for Flight 5.7V Variant are fitted
solder on radial capacitor for input buck
solder on test input leads for buck testing
verify pin 1 on chips aligns with indicator
plug/unplug cycles on connectors for reliability
Power Testing with DMM
make sure no power rails are shorted to ground or each other with DMM
slowly increase voltage (with low current limit, 100mA max) on buck input, check its not drawing excessive current/power (ensure no output load)
probing output net for voltage stability with DMM then oscilloscope
scope switch node
then slowly increase voltage on internal 5v rail, verify the internal 3v3 rail turns onone this works for all boards
Power Testing with Oscilloscope
load test on buck converter: use eload to fully saturate the buck and verify you get the output current expected
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