4.1 Power Distribution

SAM L22 Xplained Pro has three power sources; EDBG USB, Target USB, and/or external 5.0V. The kit will automatically select a source to draw power from. The kit has two on-board 3.3V voltage regulators, one for the EDBG and XAM and one for the ATSAML22N18A and other peripherals.

An on board super capacitor (47mF) is charged to 3.3V from the target 3.3V net. The super capacitor is connected to PB03 (VBAT) through a selection header and is intended for backup use in sleep modes.