An ATTiny85-based LED Matrix “backpack” PCB design.
![](https://jasonamri.com/wp-content/uploads/2019/07/led-matrix.gif)
![](https://jasonamri.com/wp-content/uploads/2019/07/led-matrix-back-1024x993.jpg)
Easily re-programmable, low-cost BOM, simple construction, and tons of fun! This small PCB fits to the back of an LED Matrix and drives animations.
![](https://jasonamri.com/wp-content/uploads/2019/07/led-matrix-inside-1024x1024.jpg)
At the heart of the design is an atTiny85 microcontroller. It holds the animation and library to drive the matrix. In addition, a MAX7219 LED driver is used to interface with the matrix.
![](https://jasonamri.com/wp-content/uploads/2019/07/led-matrix-front-1024x1024.jpg)
Animations can be uploaded over USB and programmed in the Arduino IDE.
Want to build it yourself!? EAGLE schematic and board layout can be found below.
Parts:
- 1x ATTiny85 Microcontroller (SMD)
- 1x MAX7219CNG (THT)
- 1x 8*8 LED Matrix (I used the LTH1388BSR)
- 2x 3.6v Zener Diode (for USB Bus)
- 1x MicroUSB Connector (SMD)
- 1x 6mm Tact-switch (SMD)
- 2x 68 ohm resistor (0805)
- 1x 30k ohm resistor (0805)
- 1x 1.5k ohm resistor (0805)