RGB mood lamp

Blend red, green and blue with PWM for any colour.

Open in Circuit Lab Simulator

Interactive Simulation

RGB colour mixerarduino-uno

Open in Lab

Required Components Checklist

Assembly Steps

One resistor per colour

Pins 9, 10 and 11 each through 220 Ω to R, G and B. The long common leg goes to GND.

Mix colours

analogWrite each channel 0–255. (255, 0, 255) is magenta; (255, 160, 0) is orange.

Animate

Cross-fade between colours in loops.

Arduino Sketch

const int R = 9, G = 10, B = 11;

void color(int r, int g, int b) {
  analogWrite(R, r);
  analogWrite(G, g);
  analogWrite(B, b);
}

void setup() {
  pinMode(R, OUTPUT);
  pinMode(G, OUTPUT);
  pinMode(B, OUTPUT);
}

void loop() {
  for (int i = 0; i < 255; i += 5) { color(255 - i, i, 0); delay(30); } // red → green
  for (int i = 0; i < 255; i += 5) { color(0, 255 - i, i); delay(30); } // green → blue
  for (int i = 0; i < 255; i += 5) { color(i, 0, 255 - i); delay(30); } // blue → red
}

Challenges & Extensions

Ready to take this project further? Try these challenges:

•Pick colours with three potentiometers.
•Add a button that cycles through favourite colours.
•Make a 'breathing' mode.