NEW PRODUCTS – Adafruit Small & Mini 8×8 Pure Green LED Matrixes w/I2C Backpack – What’s better than a single LED? Lots of LEDs! A fun way to make a small display is to use an 8×8 matrix or a 4-digit 7-segment display. Matrices like these are ‘multiplexed’ – so to control 64 LEDs you need 16 pins. That’s a lot of pins, and there are driver chips like the MAX7219 that can control a matrix for you but there’s a lot of wiring to set up and they take up a ton of space. Here at Adafruit we feel your pain! After all, wouldn’t it be awesome if you could control a matrix without tons of wiring? That’s where these adorable LED matrix backpacks come in. We have them in three flavors – a mini 0.7″ 8×8, a small 1.2″ 8×8 and a 4-digit 0.56″ 7-segment. They work perfectly with the matrices we stock in the Adafruit shop and make adding a bright little display trivial.
The matrices use a driver chip that does all the heavy lifting for you: They have a built in clock so they multiplex the display. They use constant-current drivers for ultra-bright, consistent color (the images above are photographed at the dimmest setting to avoid overloading our camera!), 1/16 step display dimming, all via a simple I2C interface. These backpacks come with address-selection jumpers so you can connect up to four mini 8×8’s to eight 7-segments or eight 1.2″ 8×8′s together (or a combination, such as four mini/1.2” 8×8’s and four 7-segments, etc) on a single I2C bus.
These product kits comes with:
A bit of soldering is required to attach the matrix onto the backpack but it’s very easy to do and only takes about 5 minutes.
Of course, in classic Adafruit fashion, we also have a detailed tutorial showing you how to solder, wire and control the display. We even wrote a very nice library for the backpacks so you can get running in under half an hour, displaying images on the matrix or numbers on the 7-segment. If you’ve been eyeing matrix displays but hesitated because of the complexity, this is the solution you’ve been looking for!
Make a scrolling sign, or a small video display with the 8×8 gridded pure green LED matrix. Only 1.2″ on a side, it is quite visible but not so large it wont plug into a breadboard! And you will squeak with delight when you hold this adorable miniature LED matrix. 0.8″ square, it’s got everything a big LED matrix has, but bite sized! 64 pure green 250mcd LEDs are contained inside the plastic body, in an 8×8 matrix. There are 16 pins on the side, 8 on each, with 0.1″ spacing so you can easily plug it into a breadboard with plenty of space to wire it up.
These LEDs have a deeper green coloring, it’s a beautiful shade but the process is different than our other mini or 1.2″ green LED matrices so be aware the colors wont match up.
Since the display is in a grid, you’ll need to 1:8 multiplex control it. We suggest either using a 74HC595 and TPIC6B595 (using the 74HC’ to control the 8 anodes at once and then using the TPIC’ to drive one cathode at a time) or just using a single MAX7219 which will do the multiplexing work for you.
The Arduino playground has a nice set of tutorials introducing the MAX7219 and 8×8 LED matrices
In stock and shipping now!