Changes

AXELULite SOM is powered by VIN_3V3 that, in turn, originates at carrier board level. VIN_3V3 is connected to the net VIN_SOM through a shunt resistor (R12) that is used by power measurement circuit. Circuitry  The rest of the circuitry is powered by 3.3V rail that is turned on via U70 switch. This switch - enabled by the SOM_PGOOD signal - is used to implement proper power up sequence, as described [[Power_(AXELULite)|here]]. A tiny microcontroller (U68) is used to implement a voltage monitoring circuit to verify that the difference between native AXELULite I/O voltage (SOM_3V3_IO) and 3.3V does not exceed 300mV, as per [[Power_(AXELULite)#Introduction|design requirement]]. In case this condition is not met, the microcontroller triggers a full power up cycle via PMIC_PWRON.