Using the DC supply input to power the Arduino

The DC supply input connector can be used with an AC-to-DC power adapter or a battery to power the Arduino. The connector has a female 2.1 mm center-positive plug. While the Arduino operates at 5 volts a maximum input of 20 volts can be used; however, as was stated earlier, it is recommended to not use more than 12V.

We can use an AC-to-DC adjustable power adapter like the one shown in the following photograph to power the Arduino using the DC supply input connector:

With this adapter, you can adjust the output power to the desired voltage. You can find power supplies similar to this online or at most stores that sell electronic items.