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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 slowly increase voltage on internal 5v rail, verify the internal 3v3 rail turns on
Oscilloscope
scope switch node
probing output net for voltage stability with oscilloscope
E-load
load test on buck converter: use eload to fully saturate the buck and verify you get the output current expected (up to 1A)
Efficiency calculations: 12V, 24V, 50V
Oscilloscope
scope switch node
probing output net for voltage stability with oscilloscope
then handoff to firmware for testing
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