An Introduction To Individually Addressable LED Matrices

The most fascinating project you can build is something with a bunch of blinky hypnotic LEDs, and the easiest way to build this is with a bunch of individually addressable RGB LEDs. [Ole] has a great introduction to driving RGB LED matrices using only five data pins on a microcontroller.

The one thing that is most often forgotten in a project involving gigantic matrices of RGB LEDs is how to mount them. The enclosure for these LEDs should probably be light and non-conductive. If you’re really clever, each individual LED should be in a light-proof box with a translucent cover on it. [Ole] isn’t doing that here; this matrix is just a bit of wood with some WS2812s glued down to it.

To drive the LEDs, [Ole] is using an Arduino. Even though the WS2812s are individually addressable and only one data pin is needed, [Ole] is using five individual data lines for this matrix. It works okay, and the entire setup can be changed at some point in the future. It’s still a great introduction to individually addressable LED matrices.

If you’d like to see what can be done with a whole bunch of individually addressable LEDs, here’s the FLED that will probably be at our LA meetup in two weeks. There are some crazy engineering challenges and several pounds of solder in the FLED. For the writeup on that, here you go.

8 thoughts on “An Introduction To Individually Addressable LED Matrices

  1. Any led matrix can be driven with one data pin and a combination of shift registers anyway, and it is as simple an ‘introduction’ as it gets, what’s the huge discovery here?

    1. If you just want to turn a LED on or off, shift registers are great. But if you want 8-bits of resolution per color then you’re in for some work.
      Controlling the color of each LED with shift registers is a challenge.
      One can control the color of LEDs using shift registers but there’s a limit of how many you can control this way before the refresh rate causes a noticeable flicker.
      I can barely control 64 RGB LEDs with shift registers and maintain 8-bits resolution per color and this is driving the shift registers from assembly. (Honestly the 8-bit color kind of flickers. I think my 8×8 displays look better when using 5-bit color.)
      Being able to assign a color to an individual LED with these individually addressable LEDs is a huge plus.
      I think there are applications were shift register controlled LEDs have an advantage over individually addressable LEDs. For one thing, one can adjust the overall brightness of a display when using shift registers (by pulsing the enable pin) without losing color depth. Reduce the brightness of WS2812 LEDs also reduces the possible color depth.

    2. Why do you expect a huge discovery? On a good day there are 10-15 posts here to enjoy. There are several ways to drive LEDs, shift registers are one, so are specialized ICs, so are modules with serial interfaces.

      Why be both combative and overly reductionist?

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