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zener diode taken off, and the short stopped after removing
testing the diode for bias, seems like the diode was the problem
25-07-2023
controller board is not the problem, correctly outputs 3V3 (when testing independently)
when the controller board is connected and the PD is supplied with a 12V, the 3V3 voltage rail is supplied ~1.8-1.9V when the controller board is connected, even the 3V3 rail on the CB is 1.8-1.9V(with test points both on the pd and cb)