Read the world · 05 / 16
RGB LED: Mix Red, Green & Blue
Adjust three PWM channels to mix RGB light. Make red, yellow and white, and see how each channel changes the LED color.
Control three PWM channels independently.
Understand it
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.
Your experiment
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
Sketch
This sketch illustrates the hardware logic. The workbench runs its corresponding teaching model, not a C++ compiler.
void setup() {
pinMode(9, OUTPUT);
pinMode(10, OUTPUT);
pinMode(11, OUTPUT);
}
void loop() {
analogWrite(9, 180);
analogWrite(10, 90);
analogWrite(11, 220);
}Quick check
Which channels make yellow in this model?
Show explanation
Red and green, with blue at zero. This is additive mixing of light, so the result differs from mixing paint.