Q: What happens when AC is the only power source and is disabled through I2C by setting PPATH1[4] = 1 and POWER_ON remains high?

A: SYS will begin to ramp down to UVLO at which point the converters/LDOs will shut off and the I2C registers will reset to their default values (including PPATH1) then the PMU will turn back on to it's default state.

The same applies if powered from only USB instead of AC and PPATH[5] is set.

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