U14 (on the right) converts the 5V from USB down to 3.6V ("battery level").
U1 (on the left) converts the 3.6V from U14 down to 3.3V ("logic level").
So, check those and report back.
U14 on the right: 3.54v output on upper left output pin, source voltage on lower left pin: 4.39v
U8 on the left: 3.28v output on upper left output pin, source voltage on lower left pin: 3.54v
Additional voltages from the current jumpers in the middle of the board:
3.29v VDD_IO CURRENT
3.54v VDD_BAT CURRENT
1.15v VDD_CHG CURRENT (battery switch is off and no battery is installed)
0.00v BATTERY CURRENT (battery switch is off and no battery is installed)
4.39v USB CURRENT
Something I haven't tried yet... Now that I've removed that TI codec chip, I'm going to see if powering it on its 5v VBUS pin works again.
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