Driving 4 RGB LEDs from 5V Arduino outputs while not exceeding the 40mA maximum current limit per pin

@nemethakos

9 years ago

https://everycircuit.com/circuit/6533851438645248

Generic common anode RGB LED characteristics: Vred = 2V, Vgreen+blue=3V, Ired+green+blue=20ma. NPN BJTs: 2N2222, Hfe=50@150mA. Rred~150Ohm, Rgreen+blue~100Ohm