What is it?

It's 3x3 matrix LED with 8 lighting patterns selectable through a button. It's every thing mounted into the same pcb, including the battery.

How it works?

It uses 6 pins of the pic to turn on/off the leds. Each column is common cathode and each row common anode, so when some row is high and the rest low, and some column is low and the rest high you can bright just one led.

The chip use this concept to produce pattern, but instead of brighting all the leds at same time, it does row by row, quick enough to see it like whole picture

Why did you make it?

I made this prototype to understand how led screen works, and also to experiment with LED's and small batteries.

What makes it special?

It's small pcb (5x8cm) all integrated light system