Power Domains

Figure 1. Power Domain Overview

The AVR DD Family of devices has several power domains with the following power supply pins:
VDD

Powers I/O lines, XOSCHF and the internal voltage regulator

VDDIO2 Powers I/O lines, optionally at a different voltage from VDD

The ground pins, GND, are common to VDD and VDDIO2.

A subset of the device I/O pins can be powered by VDDIO2. This power domain is independent of VDD. Refer to the MVIO - Multi-Voltage I/O section for further information.

For recommendations on layout and decoupling, refer to the Hardware Guidelines section.