3.2 Power Sources
The kit can be powered by different sources. By default the kit will have a 5V supply and the voltage is taken directly from the USB port through a 500 mA PTC fuse. The voltage from the USB connector can vary between 4.4V to 5.25V (according to USB spec).
If other voltages are required, the kit must be disconnected from the USB to avoid damage or contention to the USB power. The mEDBG must also be disconnected from the target section of the board. The board can be powered by applying a voltage to one of the power connections on the board, according to the table below. To avoid any power leakage through the mEDBG, this should also be disconnected by removing the resistors shown in Figure 3-3. For placement of power connections, see Xplained Nano Standard Pinout.
| Power Connection | Description |
|---|---|
| VUSB | USB Voltage output when USB is connected (behind a PTC fuse). Can be used as power input when USB is not used. |
| VREG | Regulated voltage from VUSB. If the kit does not have a regulator, this is directly connected to VUSB. |
| VCC | Target voltage supply. By default, connected to VREG through a 0Ω resistor. Apply external voltage here if the resistor is removed. |
