• DESCRIPTION

  What's better than a single LED? Lots of LEDs! A fun way to make a small display is to use an 8x8 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 two flavors - a mini 8x8 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. The backpacks come with address-selection jumpers so you can connect up to four mini 8x8's or eight 7-segments (or a combination, such as four mini 8x8's and four 7-segments, etc) on a single I2C bus.
  
  The product kit comes with:

  • A fully tested and assembled LED backpack
  • Ultra-bright 8x8 yellow matrix
  • 4-pin header

  A bit of soldering is required to attach the matrix onto the backpack but its 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, his is the solution you've been looking for!

TECHNICAL DETAILS

• This board/chip uses I2C 7-bit address between 0x70-0x77, selectable with jumpers

Backpack Dimensions:

• 20mm x 28mm x 4mm / 0.8" x 1.1" x 0.2"
• Mounting Holes: 12mm x 22mm / 0.5" x 0.9"

Datasheets, schematic, EagleCAD PCB files, and Fritzing available in the product tutorial

LEARN

Trinket / Gemma Space Invader Pendant

Itsy bitsy electronic jewelry!

Animating Multiple LED Backpacks

Lights! Action! MORE LIGHTS! MORE ACTION!

Matrix and 7-Segment LED Backpack with the Raspberry Pi

Adafruit LED Backpacks

Control small LED matrices with ease