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GND, 3V3, 5V, and 12V test points are all isolated from each other, tested with the multimeter continuity test.
Removed R23. This is a 0 ohm resistor between the Current Sense output of the load switch and the input of the MCU for measurement. Why do we need to remove this (Liam Hawkins)?
Without the controller board connected, 12V tested good. Installing the controller board, both 3V3 and 12V are good!
5V does not seem to be powering on. It slowly rises to 1.8V, and then stays there. I was artificially turning on EN with another power supply connected to wires I had soldered to R3. I realized that the wire also touched R2, and caused this behaviour. Fixing this, the 5V converter works and we get 4.935V.
86mV Vpp on no load, 20mV Vpp for both 1A and 2A loads. Oscilloscope was set to AC coupled, triggering on rising edge, with a 1X probe connected to the GND with the probe’s alligator clip.
Note - Good page on measuring power supply noise: https://www.edn.com/testing-a-power-supply-noise-part-2/
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^ No load
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^ 1A Load
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^ 2A Load
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