Author Andrei
17/06/2019

If you are into electronics, I bet you've seen a lot of badges with LCDs, OLED display, LEDs and so on. AmalMathew posted on Instructrables his work on an LED dor matrix badge. As he says on the tutorial post:

"Are you running an event ,competition or even hosting a birthday party ? Badges are versatile item that can make introductions and celebrations that much easier .You would never begin a conversation with "hello , my name is ............." so why should your badge?"

In this project, he will show us how he built a badge-sized ATtiny85-based LED matrix display (5x4 matrix). He used Charliplexing technique for driving 20 LEDs using ATtiny85.

To make this project you will need hardware components such as one ATtiny85m, aCoin Cell Battery CR2032, some 3mm LED, a CR2032 Coin Cell Holder, 8 pin DIP IC Socket, a slide switch, five 100 ohm resistors and for the software, you will need the Arduino IDE and of course, a soldering iron.

As he said, he used to control the LEDs. Charliplexing is a technique for driving a multiplexed display in which relatively few I/O pins on a microcontroller are used, e.g. to drive an array of LEDS. The method uses the tri-state logic capabilities of microcontroller in order to gain efficiency over traditional multiplexing.

He used KiCad for PCB Design. The edge cut were made using .DXF file which was designed and generated using Autodesk Fusion 360. The final size of PCB badge was 55*86mm which id ok. If you want to see more about this and all the steps for the tutorial, check his post on Instructables with more photos, the code and schematic.

Apart this post, if you have your own project and you need good quality PCBs, consider using the services of PCBWAY.com which will offer you quite good services, I use their services a lot of my PCBs.

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