RGB LED: Mix Red, Green & Blue

Why it’s here

Control three PWM channels independently.

How it works

Three channels are set independently. Red plus green produces yellow light; equal nonzero values produce neutral light. The model approximates visible color, not LED spectral response or calibrated brightness.

Try it

1. Open this experiment
2. Set red to 255 and the other channels to 0. Add green at 255, then blue at 255, observing each color change.

Connections

• D9 ~ — Red through resistor
• D10 ~ — Green through resistor
• D11 ~ — Blue through resistor
• GND — Common cathode

Example sketch

void setup() {
  pinMode(9, OUTPUT);
  pinMode(10, OUTPUT);
  pinMode(11, OUTPUT);
}

void loop() {
  analogWrite(9, 180);
  analogWrite(10, 90);
  analogWrite(11, 220);
}

Check your understanding

Which channels make yellow in this model?