I've build a 10x10 RGB Led Matrix Simulator on circuits.io because I've allready build a 10x10 RGB Matrix in real life. This one is for testing code and not damaging anything on the real one. So basically this Matrix works with 5 Shift register to control 100(300) leds by only 3 pins.

Here the link:

https://circuits.io/circuits/2924748

Step 1: How the Circuit Is Build Up

So we've a 9V power supply and a 5V regulator. The 9V are going inro the matrix itself. 5V is needed to supply the logic side with energy. The arduino & shift registers are connected to 5V.

Step 2: How the Circuit Is Build Up

The arduino connects with 3(5) pins to the logic. Data, Latch, Clock are nessacary and I've added OE and clear.

Step 3: How the Circuit Is Build Up

The logic is build a save way with BJT's before every connection so the shift registers wont get damaged.

Step 4: Finished LED Matrix

So here are some photos of the finished real life version of the Matrix. It works fine for now. Only thing I needed to change was the controller. The 16MHz arduino is a bit slow to control that amount of leds. I've bought a Teensy 3.6 with 180MHz and now everything works fine.