Charlieplexing LEDs- The theory

Step 7 References

There are lots of references about charlieplexing on the web.
In addition to the links at the front of the article, some of them are:

The original article from Maxim, this has a lot to say about driving 7 segment displays which is also possible.
http://www.maxim-ic.com/appnotes.cfm/appnote_number/1880

A wiki entry
http://en.wikipedia.org/wiki/Charlieplexing

Comments

[Tail_wag]

Simply an excellent article. Can you confirm that we cannot turn on all LED's in the matrix at the same time using this method? Thanks.

[rgbphil]

You should only keep one LED on at a time if you have no buffering on your micro, or else the current draw will exceed the micro design tolerances.

However if you read the front page, there is quite a thread on lighting several LEDs at once with a charlie matrix. It is possible, but you should really buffer the control lines.

Check out the comments on this and follow the links back to the bloke who put me right in this regard.....he's got some great examples of more advanced charliplexing on his pages and probably a better explanation than I could have done.

[Eliche]

Excellent explanation, very easy to follow and very helpful.

[codongolev]

man.... that explained it so well. thanks!

[RobbMeex]

I just put this thing together!! Thanks a bunch. I was looking for a simple two digit display for a GPS speedometer.

[haooken]

Excellent explanation. I'll definitely have to give this a try.

[ricecooker7654]

i first i was slightly intimidated by ur explanation but after reading it, i feel like i can teach my electronics teacher this concept. thanks -drew

[aolinger]

I've got it, and I'm a complete new to to microcontrollers and electronics! Thanks for this great explanations! Alex

[51fordf2]

Thanks, about the easiest to understand explanation I have seen. R

[alain91]

Excellent article. Thanks a lot !