Datasheet

0.54" Alphanumeric

This version of the LED backpack is designed for two dual 14-segment "Alphanumeric" displays. These 14-segment

displays normally require 18 pins (4 'characters' and 14 total segments each) This backpack solves the annoyance of

using 18 pins or a bunch of chips by having an I2C constant-current matrix controller sit neatly on the back of the PCB.

The controller chip takes care of everything, drawing all the LEDs in the background. All you have to do is write data to

it using the 2-pin I2C interface.

There are three address select pins so you can select one of 8 addresses to control up to 8 of these on a single 2-pin

I2C bus (as well as whatever other I2C chips or sensors you like). The driver chip can 'dim' the entire display from 1/16

brightness up to full brightness in 1/16th steps. It cannot dim individual LEDs, only the entire display at once.

Attaching the Backpack

When you buy a pack from Adafruit, it comes with the

fully tested and assembled backpack as well as two dual

14-segment display in one of the colors we provide (say,

red, yellow, blue or green). You'll need to solder the

matrix onto the backpack but it's an easy task.

Remove the parts from packaging and place the LED

matrices OVER the silkscreen side. DO NOT PUT THE

DISPLAY ON UPSIDE DOWN OR IT WONT WORK!!

Check the image below to make sure the 'decimal

point' dots are on the bottom, matching the silkscreen.

(https://adafru.it/l3c)