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The Cube was not my idea, I stumbled upon a video of a LED cube while researching the arduino. I found the LED cube so awesome that I decided to make one myself.

Now it has been build, I can understand why you can't really buy one. If you find a company that produces it, it is ridiculously expansive. And that is because it takes a lot of time just building the thing.

To give you some idea, I used 512 blue diffused 5mm LED's and 55 meters of silver-plated wire. This equals to hundreds of hours of pure soldering fun :-)

Here is a video of a first demo of the end product:

The basics

The basic principle behind this cube is multiplexing. Simply put: all the columns are cunnected (8×8=64 columns) and all levels are connected (8 levels). So you have 64 connections on the bottom and 8 connections for the levels.

All you have to do to turn one LED on, is to put ~2,5Volt on one column and 0Volt on the corresponding level. For the second LED you do this again, and for the next again … And so on.

If you do this a couple of hundred times per second, the human eye does not see it blinking. The human eye thinks the LED's are constantly on. This phenomenon is called Persistence of vision .

The intelligence be hind it all is an Atmega328P microprocessor. This sounds like a lot of work but actually you can buy a PCB with a micro-controller, serial port for programming and all basic components for using the Atmega328P quite cheaply. I bought a couple at avmicrotech on e-bay. You need only one board like the “ATMEL ATMEGA328 Arduino Duemilanove bootloader” for this project.