How to use external power supply for Arduino

How to use external power supply for Arduino? How to provide external power to sensor, relay, servo motor ...

Answer

When should use the extra power supply

Power from 5v pin of Arduino may NOT be enough in some cases. For example:

  • The sensors/devices consumes much energy
  • A large number of sensors/devices are connected to Arduino

How to connect to the external power supply

In these cases, we MUST use the external powers for sensors/devices. To use multiple power source, it need to follow the following conditions:

  • MUST NOT connect 5V of the external power supply to 5V of Arduino
  • MUST connect GND of the external power supply to GND of Arduino

Example

  • The external power supply for servo motor
Arduino external power supply for servo motor

This image is created using Fritzing. Click to enlarge image

  • The external power supply for relay
Arduino external power supply for relay

This image is created using Fritzing. Click to enlarge image

  • The external power supply for LED strip
Arduino external power supply for LED strip

This image is created using Fritzing. Click to enlarge image

Buy Arduino

1 × Arduino UNO Buy on Amazon
1 × USB 2.0 cable type A/B Buy on Amazon
1 × Jumper Wires Buy on Amazon
Please note: These are Amazon affiliate links. If you buy the components through these links, We will get a commission at no extra cost to you. We appreciate it.

The Best Arduino Starter Kit

※ OUR MESSAGES