What's cooler than a single LED? A bunch of them! A great way to create a small display is by using an 8x8 matrix or a 4-digit 7-segment display. These matrices are multiplexed, which means you need 14 pins to control all the seven-segment LEDs. That's a lot of pins! There are driver chips like the MAX7219 that can handle the matrix for you, but they involve a lot of wiring and take up a lot of space. At Adafruit, we understand your frustration. What if you could control a matrix without all that wiring? That's where our cute LED matrix backpacks come in. We offer two types: a mini 8x8 and a 4-digit 0.56' 7-segment. They work perfectly with the matrices in our Adafruit shop, making it easy to add a bright little display. The matrices use a driver chip that does all the hard work. They have a built-in clock for multiplexing the display. With constant-current drivers, they provide ultra-bright, consistent color (the images above are taken at the dimmest setting to avoid overloading our camera!), and 1/16 step display dimming, all through a simple I2C interface. The backpacks come with address-selection jumpers, allowing you to connect up to four mini 8x8's or eight 7-segments (or a combination) on a single I2C bus. The product kit includes a fully tested and assembled LED backpack, an ultra-bright 4-digit 0.56' tall green seven-segment display, and a 4-pin header. A little soldering is needed to attach the matrix to the backpack, but it's very easy and only takes about 5 minutes. And, as always with Adafruit, we have a detailed tutorial on soldering, wiring, and controlling the display. We've also written a great library for the backpacks, so you can start displaying images on the matrix or numbers on the 7-segment in under half an hour. If you've been interested in matrix displays but were put off by the complexity, this is the solution you've been waiting for!
Using this product is a breeze. First, you'll need to do a bit of soldering to attach the 4-digit 7 - segment display to the LED backpack. It only takes about 5 minutes. Once that's done, you can connect it to your device using the 4 - pin header. The backpacks come with address - selection jumpers, so you can connect multiple displays on a single I2C bus. To start using it, refer to our detailed tutorial. It will show you how to solder, wire, and control the display. We've also written a library for the backpacks, which can get you up and running in under half an hour. When taking pictures of the display, remember that it's very bright. The images in our description are taken at the dimmest setting to avoid overloading the camera. For maintenance, keep the display clean and avoid exposing it to extreme temperatures. If you have any issues, our support team is always here to help.
