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Topic: 112 RGB LED Coffee Table (Read 37756 times) previous topic - next topic


where do you buy a tlc5940, and what is it?


Absolutely great work. I've actually been working on a smaller version of this same idea. How many TLCs are you running? Each chip has 16 channels. And it looks like each LED consumes one channel. So 112/16 is 7 chips? My build is using 25 LEDs. The big difference is that my LEDs are common anode LEDs. So each color has its own channel on the TLC and are connected together across columns. My anodes are connected together down the rows. So I basically set my TLCs, pulse a row for 2ms or so, clear the row, set the TLC for the next row, pulse the next row, etc. The problem I'm running in to is my colors are not consistent at all. If I set my display to white, I get some white, some bluish, some greenish, some redish, some don't turn on much at all, blah blah blah. Any ideas why this might be happening? I guess switching to common cathode LEDs might be an easier fix...


Mar 01, 2010, 05:49 am Last Edit: Mar 01, 2010, 05:54 am by SoCentral2 Reason: 1
I didn't realize I needed one of these until I read this post.  :)

Jeremy --> http://focus.ti.com/lit/ds/symlink/tlc5940.pdf
          |-> http://uk.rs-online.com/web/0422283.html
                & only £2.16!



The TLC5940's have dot correction which you can set on the individual channels to correct for the varying LED colors. Don't ask me how to do it though, im just starting with these. Also the TLC5940's are in very short supply and most major distributors are on back order. Mouser had some TLC5941NT's (dip package) which are essentially the same chip, however their max Ic is 80mA instead of 120mA and they don't have the EEprom to store the dot correction so you would have to set that in the setup each time.


how did you link processing to the arduino? i guess i could just google that huh? i'll try that too. ;)


Wow, very impressive.  Definitely the best LED coffee table I have seen thus far.


The 5940 is pretty cheap - but when there are none available you can advertise them for whatever you fancy.  I've had an order outstanding with RS now for over 2 months. :(


Wow that is amazing. I just got started learning how to write programs and such about a month ago but the reason I even started was because of an idea I had that is pretty much identical to this. I've got a lot of learning to do but one day I'll get there lol. Amazing and well done.



Great project Joe! I'mcurrently trying to build a similar setup, but I was going to use PIC controllers instead and individual red, green, blue LED's instead of common cathode ones. I took a look at the code and schematic but I don't quite get it all. How is the master passing patterns to the slave? How is the Slave passing patterns to the LED driver? Could you send me a diagram of how the chips are wired together?

Thanks, and keep up the good work!


Excellent build. This is my motivation for a wall panel I'm building.


Hello, Nice work !
Which model of LED do you use?


that's really cool, i'd like to build something similar,
is that the entire circuit schematic, where are the LEDs ?


Hey Joe, that is seriously great.  I mainly want to know how you did the software interface.  The real-time response is very impressive.


Very cool! And really nicely done, great work! I too thought the realtime respone was impressive!

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