Power Supplies

The Atmel SAM L21 has several different power supply pins:

The same voltage must be applied to both VDDIN and VDDANA. This common voltage is referred to as VDD in the datasheet.

When the Peripheral Touch Controller (PTC) is used, VDDIO must be equal to VDD. When the PTC is not used by the user application, VDDIO may be lower than VDD.

The ground pins, GND, are common to VDDCORE, VDDIO and VDDIN. The ground pin for VDDANA is GNDANA.

For decoupling recommendations for the different power supplies, refer to the schematic checklist.