3.4.2 Xplained Pro Power Header
The power header can be used to connect external power to the SAM R21 Xplained Pro kit. The kit will automatically detect and switch to any external power if supplied. The power header can also be used as supply for external peripherals or extension boards. Care must be taken not to exceed the total current limitation of the on-board regulator when using the 3.3V pin.
| Pin number | Pin name | Description |
|---|---|---|
| 1 | VEXT_P5V0 | External 5V input |
| 2 | GND | Ground |
| 3 | VCC_P5V0 | Unregulated 5V (output, derived from one of the input sources) |
| 4 | VCC_P3V3 | Regulated 3.3V (output, used as main power supply for the kit) |