In high voltage mode, the output from VREGH can be used to supply external circuitry from the VDD pin.
As illustrated in High voltage mode, external circuitry can be powered from the VDD pin. The VDD output voltage is programmed in the register UICR.VREGHVOUT.
The supported output voltage range depends on the supply voltage provided to the VDDH pin. The difference between voltage supplied on the VDDH pin and the voltage output on the VDD pin is defined by the VREGH,DROP parameter in Regulator specifications, VREGH stage.
Supplying power to external circuitry is allowed in both System OFF and System ON mode.
Note:
The maximum allowed current drawn by external circuitry is dependent on the total internal
current draw. The maximum current that can be drawn externally from REGH is defined in Regulator specifications, VREGH stage.