RGB LED Module
Simple common-cathode RGB LED breakout for basic color mixing.
A basic 4-pin RGB LED breakout used for teaching PWM color mixing and simple status-indicator projects.
Specifications
| Type | Common-cathode on most breakout modules (common-anode variants also exist — verify with a multimeter before wiring) |
| Forward voltage | ~2V (Red), ~3.2V (Green), ~3.2V (Blue), typical |
| Control | 3 independent PWM channels, one per color, each through its own current-limiting resistor |
| Current-limiting resistor | ~220Ω-330Ω per color channel at 5V logic — a shared value across R/G/B works fine even though forward voltages differ slightly |
Pinout
| Pin | Name | Description |
|---|---|---|
| 1 | R | Red channel — through a current-limiting resistor to a PWM pin |
| 2 | COM | Common cathode (to GND) or common anode (to VCC), depending on your specific module |
| 3 | G | Green channel — through a current-limiting resistor to a PWM pin |
| 4 | B | Blue channel — through a current-limiting resistor to a PWM pin |
On a common-anode module, drive each color LOW to turn it on rather than HIGH — inverted from the common-cathode wiring most beginner tutorials assume.
Variants
Always check whether your specific RGB LED module is common-cathode or common-anode before wiring — code and PWM logic written for one will produce inverted or wrong colors on the other, and it's not visually obvious which type you have. If a project needs more than a couple of independently-colored LEDs, addressable WS2812B modules control many pixels over a single data pin and scale far better than wiring 3 PWM pins per discrete RGB LED.
| Variant | Price |
|---|---|
| Common-cathode RGB module (this listing) | ~$0.50-1.50 |
| Common-anode RGB LED | ~$0.50-1.50 |
| WS2812B addressable LED | ~$5-15 per meter |