Led cube is actually nothing new. Many of us think that building a good size electronic device is almost an electronic ceremony. Not so many people can find time or have the ability to get out. We are pleased to draw your attention to a lovely build that shows all the processes, problems, and solutions involved.
Building a small cube is a bit trivial, especially without considering PWM color mixing, but as simple mathematics shows, as the number of LEDs on each side increases, the total number will soon become quite large. More LEDs require more power and greatly increase the complexity of control. Like this larger matrix built by 16 x 16 x 16 LEDs, there are 4096 in total. Even with clever multiplexing technology, using ordinary RGB LED driver will be a nightmare, but fortunately, you can buy an indexable led through-hole package similar to the ubiquitous SMT LED based on ws2812. These are based on pd9823 controllers, which can be programmed as ws2812 at least according to this analysis. Now, you can simply link a list of LEDs and transfer the control signal from the led to the nearest neighbor.
Early in the video build log, you’ll notice that you need four power modules to power the juice. If we assume that each LED consumes 60 Ma on all white (the data of this product link shows a peak of 100 mA), this is still a total power of 246 a or about 1 kW. The video does show a peak power measurement, about this number, for the entire array of all white, so the mathematics seems to be correct.
The control is carried out through a teensy 4.0 using the flexio function of imxrt1060rm CPU and a set of 74ahct595 shift registers. If necessary, each channel provides 32 channels and up to 1000 LEDs. Roughly speaking, using DMA with flexio, teensy can drive up to 1 million led updates per second, about 32 channels per channel, 100 LEDs per channel, and update at the speed of 330 frames / second, so there are sufficient resources. All of these have little CPU intervention, which is used to process UI based on 2.4-inch LCD and run animation. If you ask us, it looks great. You can check out the description of the firmware in the firmware section of the GitHub project. The 3D printing fixture allows you to bend and cut led leads, and fix and align LED column units, so there are indeed enough details for anyone to copy this, as long as you can swallow the cost of all these LEDs.