RGB LED Driven by Only Three Microcontroller Pins

In this project, the RGB LED contains 3 LEDs encased in one shell which looks like a single white LED except that it has for leads where one lead is for the common ground and one for each LED.

During the operation, the average current through each of the LEDs determines its light output such as its contribution to the total output color. Almost any other color can be created by scrolling the average current through each LED. The ICSP connector is used to program the PIC in-circuit.

Almost any other color can be created by varying the current through each LED but at close range, only the individual colors of each LED can be seen. The merged color view can be seen from a distance or by putting a diffuser over it. This can be done by using a small piece of baking paper which is transparent enough to let the light through and opaque enough to diffuse light from the 3 LEDs.

Each of the LEDs in the RGB LED is being driven by pulse width modulation. The average current on each LED is changed by PWM duty cycle.

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