How do RGB LED work for your project?

There have kinds of RGB LED in SHENZHEN BEST LED OPTO-ELECTRONIC CO.,LTD for your choice. Such as SMD RGB LED, which is SMD LED (surfact mount) type.  And through-hole LED(DIP LED) type. 

The package like 5mm RGB LED, 3MM RGB LED, 10MM RGB LED are all available. 

There have three chips in one RGB LED:

• 1x Red LED
• 1x Green LED
• 1x Blue LED

You can produce almost any color by combining those three colors. An RGB LED is shown in the following figure:

How to create different colors?

With an RGB LED you can, of course, produce red, green, and blue light, and by configuring the intensity of each LED, you can produce other colors as well.

Common Anode and Common Cathode RGB LEDs

There are two kinds of RGB LEDs: common anode LED and common cathode LED. The figure below illustrates a common anode and a common cathode LED.

In a common cathode RGB LED, all three LEDs share a negative connection (cathode). In a common anode RGB LED, the three LEDs share a positive connection (anode).

This results in an LED that has 4 pins, one for each LED, and one common cathode or one common anode.

RGB LED Pins

RGB LEDs have four leads—one for each LED and another for the common anode or cathode. You can identify each lead by its length, as shown in the following figure.

With the LED facing you so the anode or cathode (the longest lead) is second from the left, the leads should be in the following order: red, anode or cathode, green, and blue.

Distinguish between RGB LED common anode and common cathode

The best way to distinguish between a common cathode and common anode RGB LEDs is using a multimeter.

Put you multimeter is in continuity mode.

Place the red multimeter tip on the longest LED lead. Then, place the black tip on one of the other leads.

If the LED lights up, this means you have a common anode LED.

On the other hand,  if you have a common cathode RGB LED, you need to placed the black tip on the longest lead, and the red tip on one of the other leads (see figure below).

So, to distinguish between common cathode and common anode RGB LEDs:

• Use a multimeter in continuity mode
• If the LED lights up with the red tip on the longest lead and the black on one of the other leads – you have a common anode RGB LED
• If the LED lights up with the black tip on the longest lead and the red tip on one of the other leads – you have a common cathode RGB LED.