German-based electrical engineer Alex took to Hackaday to introduce a new project he’s been working on that he calls an “ultra tiny smart USB RGB LED display/matrix,” which is a complete overhaul of his first endeavor — 192:LED, the “extreme smart RGB LED display/matrix.”
The project came about when he pondered what to do with a handful of leftover 0404 RGB LEDs lying around: The goal is to build a very tiny 8×8 RGB LED matrix. This matrix will be controlled by UART and/or I2C (not decided yet). Besides this, there will be some ‘demo modes’ for a standalone operation.”
For the extreme version of the project, Alex soldered together a series of 0404 LEDs on a custom four-layer PCB and controlled the lot using a microcontroller (unknown) and multiplexing. Beyond the MCU and LEDs, Alex equipped the tiny matrix with a 2016-sized crystal oscillator with a pair of 0201 capacitors, 3X 0402 buffer capacitors (for Vcc), and a solder bridge to disconnect MOSI for programming.
Alex’s 192:LED redesign, however, is more streamlined than the original, and most of the hardware has been replaced with better electronics — including WS28112 LEDs in a 1515 package, and a SAM D21 MCU that’s more than capable of driving the display/matrix. He also designed an ingenious platform to program the tiny board, which consists of a 3D-printed jig, a Trinket-M0-USB-Bootloader, and an Atmel-ICE programming and debugging tool.
Alex’s Ultra tiny smart USB RGB LED display/matrix project is still a work in progress, and those interested can follow his work in the link listed above.
Build an Ultra Tiny Smart RGB LED Display Matrix with the SAM D21 was originally published in Hackster Blog on Medium, where people are continuing the conversation by highlighting and responding to this story.