What is an LED (Light Emitting Diode)


Staff member
Aug 14, 2021
Pic Credits : Digikey

About LED​

Light-emitting diodes, sometimes known as LEDs, are a type of diode that turns electrical energy into light. They are, in essence, little light bulbs that can be utilized in an electrical circuit. LEDs have a number of advantages over traditional light bulbs, including the fact that they use a lot less energy to light up and are more energy efficient, which means they convert more of the energy that travels through them into light rather than heat.

How Do Light Emitting Diodes (LEDs) Work?​

If you've ever looked at an LED, you've probably noticed that the "legs," or "leads," are different lengths. The positive side of the LED, known as the "anode," is longer, while the negative side, known as the "cathode," is shorter.


Current can only travel from the anode (positive side) to the cathode (negative side) in an LED, never the other way around. This means that if an LED is wired backwards in a circuit, it will not light up. In fact, by stopping current flow at that point, a backward LED can prohibit an entire circuit from functioning properly. If an LED fails to light up after being placed in a circuit, the first thing you should try is flipping it over.

Types of Light Emitting Diode​

  • Gallium Arsenide (GaAs) – infra-red
  • Gallium Arsenide Phosphide (GaAsP) – red to infra-red, orange
  • Aluminium Gallium Arsenide Phosphide (AlGaAsP) – high-brightness red, orange-red, orange, and yellow
  • Gallium Phosphide (GaP) – red, yellow and green
  • Aluminium Gallium Phosphide (AlGaP) – green
  • Gallium Nitride (GaN) – green, emerald green
  • Gallium Indium Nitride (GaInN) – near ultraviolet, bluish-green and blue
  • Silicon Carbide (SiC) – blue as a substrate
  • Zinc Selenide (ZnSe) – blue
  • Aluminium Gallium Nitride (AlGaN) – ultraviolet


New member
Jan 6, 2022
LED stands for light emitting diode. LED lighting products produce light up to 90% more efficiently than incandescent light bulbs. An electrical current passes through a microchip, which illuminates the tiny light sources we call LEDs and the result is visible light. Compared with conventional light sources that first convert electrical energy into heat, and then into light, LEDs (Light Emitting Diodes) convert electrical energy directly into light, delivering efficient light generation with little-wasted electricity.
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