I made this pin for my daughter, who happened to be the president of her chapter at the time of this article. It was fun to make and I learned a couple new things.
- How to make irregular PCB board shapes.
- It's my first surface mount PCB of any significant size.
I used an Atmel ATTiny85 microprocessor with 33 ws2812B led's. There are 2 switches on the front, one to reset the microprocessor and one to force it to change the light pattern. On the back are 2 JST-PH connectors, one 6-pin for the SPI programming interface and one 2-pin for the battery connection. I use a small Li-Po battery which is small enough to be attached to the back of the pin using velcro.
If you've ever used any of the WS2812B led's then you know how bright these things can be. When all 33 led's are lit, this thing is BRIGHT! You could probably see it from space. It was designed to be a pin so there's also a large pad on the back to which a run of the mill pin back is soldered.
Here is the pin when lit: