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Adafruit

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A 16×8 LED matrix backpack kit featuring two ultra-bright 1.2" red 8×8 round LED matrices on a single I2C-controlled driver board. The HT16K33 chip handles a...

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A 16×8 LED matrix backpack kit featuring two ultra-bright 1.2" red 8×8 round LED matrices on a single I2C-controlled driver board. The HT16K33 chip handles all the multiplexing, so you only need two I2C pins (SDA and SCL) to control 128 LEDs — no complex wiring required.

The backpack features constant-current drivers for consistent brightness, 1/16-step dimming control, and three address-selection jumpers allowing up to 8 backpacks on a single I2C bus. A small amount of soldering is required to attach the two matrices to the backpack board.

Key Features

  • 16×8 Red LED Matrix – Two ultra-bright 1.2" round 8×8 red matrices on one backpack
  • HT16K33 Driver – Built-in clock and constant-current drivers for consistent brightness
  • I2C Interface – Only 2 pins needed for full matrix control
  • 16-Step Dimming – Adjustable brightness from very dim to full intensity
  • Chainable – Up to 8 backpacks on one I2C bus (addresses 0x70–0x77)

Ideal For

  • Scrolling text displays and small signage
  • Compact notification and status indicators
  • Arduino and microcontroller display projects
  • Multi-backpack chainable display setups

Package Contents

  • 1× 16×8 1.2" LED Backpack (fully assembled and tested)
  • 2× Ultra-bright 8×8 round red LED matrices
  • 1× 4-pin header
Note: Some soldering is required to attach the matrices to the backpack. A microcontroller is not included — any board with I2C support will work.

Resources

Jargon buster

Plain-language definitions for the technical terms used above.

I2C
I2C is a two-wire communication bus used by many sensors and small modules. It matters because several I2C devices can share the same two wires, but each device needs a compatible address and your controller must support I2C.
LED
A light-emitting diode (LED) is a small electronic component that emits light when current flows through it in the correct direction. Because it only conducts one way, its polarity matters, and a through-hole LED must be soldered the correct way around to light up.
microcontroller
A microcontroller is a small computer on a single chip that runs a stored program and controls connected inputs and outputs such as buttons, sensors, displays and communication interfaces. In a device built around one, it is the part that executes the code and coordinates the device's behaviour.

adafruit led backpack

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