ElectronParade
The LED (Light Emitting Diode) is the most common way to add light and visual feedback to your electronic projects. They are highly efficient, come in many colors, and are essential for everything from TV screens to indicator lights on your microwave.
How LEDs Work
An LED is a specific type of diode that releases energy in the form of light when an electrical current passes through it.
However, they have two strict rules you must follow for them to work properly:
1. They are Directional (Polarized) Because an LED is a diode, electricity can only flow through it in one direction.
- The longer leg is the Anode (Positive).
- The shorter leg is the Cathode (Negative). If you plug an LED in backward, it will block the current and will not light up.
2. They Require a Current Limit LEDs are “greedy.” They will try to draw as much current as the power supply can provide. If you connect an LED directly to a 9V battery, it will overheat and burn out in a fraction of a second. Rule of thumb: Always use a resistor in series with your LED to limit the current to a safe level (usually around 20 milliamps).
Types of LEDs
LEDs have evolved far beyond standard red indicator lights. Today, you can use:
- RGB LEDs: Contain red, green, and blue elements in one package, allowing you to mix them to create almost any color using code.
- Addressable LEDs (NeoPixels): Strips of LEDs where each individual light can be controlled independently by a microcontroller.
Recommended Gear:
- Assorted Color LED Pack (5mm) - Perfect for breadboard prototyping.
- Arduino Starter Kit - The best way to learn how to control LEDs with code.