Controlling LEDs with Charlieplexing

Arduino Technology
Controlling LEDs with Charlieplexing
Screen Shot 2013-05-24 at 1.47.49 PM
Charlieplexing with Arduino.

MAKE contributor Andy has created a great tutorial to introduce you to the utility of “Charlieplexing,” a method for controlling multiple LEDs without the use of multiple microcontroller pins.  With Charlieplexing you can turn on or off one LED at a time. To light more than one LED at a time, you can scan the LEDs by turning a sequence of them on and off really fast.

Andy explains:

Charlieplexing takes advantage of the fact that LEDs are diodes: Current flows in only one direction through an LED. Connect two LEDs in parallel with each but with opposite polarity so that only one conducts (lights up) at a time and that is the basis of Charlieplexing.

Come on over to MAKE: Projects and check out Andy’s work.


Stett Holbrook is editor of the Bohemian, an alternative weekly in Santa Rosa, California. He is a former senior editor at Maker Media.

He is also the co-creator of Food Forward, a documentary TV series for PBS about the innovators and pioneers changing our food system.

View more articles by Stett Holbrook