3.1 Using the Curiosity Nano AVR128DB48

To illustrate the capabilities of Multi-Voltage I/O an AVR128DB48 Curiosity Nano is used. Schematics of the Curiosity Nano PCB can be found in the References section. To enable MVIO on this development board, perform the below steps:
  1. Remove the resistor right below the VDDIO2 label to disconnect VDDIO2 from VDD. This is resistor R204 in Figure 3-2.
  2. Connect VDDIO2 + to 3.3V of a second power voltage source.
  3. Connect VDDIO2 - to GND of a second voltage source.

Refer to the AVR123DB48 Curiosity Nano User Guide for a guide on how to reverse this process.

Any voltage between 1.8V and 5.5V may be applied to VDDIO2, but for the following examples, we will run at 3.3V.

Figure 3-1. AVR128DB48 Curiosity Nano MVIO

Figure 3-2. Snippet From the AVR128DB48 Curiosity Nano Schematic