Charlieplexing times two: GuGaplex your LEDs


Dhananjay Gadre wrote in from New Delhi with news of “GuGaplexing”, an update to the tried and true technique of Charlieplexing. GuGaplexing introduces a set of transistors into the mix to double the number of LEDs you can address:

The transistor pairs are so arranged that they provide an out of Vcc/2 at the output when the input is Z. If the input is 0, the output at the transistor is Vcc and when the input is 1, the output is 0.

This looks very cool. Check out the video that Dhananjay’s posted. There’s also an instructable that shows you how to make it.


I'm a tinkerer and finally reached the point where I fix more things than I break. When I'm not tinkering, I'm probably editing a book for Maker Media.

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