Arduino Lesson 2. LEDs - Adafruit Learning System

Skip to main content Arduino Lesson 2. LEDs LEDs

• Overview
• Parts
• LEDs
• Resistors
• Breadboard Layout
• Moving the Resistor
• Blinking the LED

• Single page
• Feedback? Corrections?
• Text View

Groups

• Learn Arduino

Featured Products view all

• Adafruit METRO 328 Fully Assembled - Arduino IDE compatible Out of Stock
• Diffused Red 5mm LED (25 pack) $4.00 Add to Cart
• Half Sized Premium Breadboard - 400 Tie Points $4.95 Add to Cart
• Premium Male/Male Jumper Wires - 40 x 6" (150mm) $3.95 Add to Cart

75 Beginner Skill guide

LEDs

LEDs make great indicator lights. They use very little electricity and they pretty much last forever.In this lession you will use perhaps the most common of all LEDs a 5mm red LED. 5Mm refers to the diameter of the LED and as well as 5mm, other common sizes are 3mm and the large fun 10mm LEDs.You cannot directly connect an LED to a battery or voltage source. Firstly, because the LED has a positive and a negative lead and will not light if they are the wrong way around and secondly, an LED must be used with a resistor to limit or 'choke' the amount of current flowing through the LED - otherwise the LED could burn out! If you do not use a resistor with an LED, then it may well be destroyed almost immediately, as too much current will flow through the LED, heating it and destroying the 'junction' where the light is produced.There are two ways to tell which is the positive lead of the LED and which the negative. 

• Firstly, the positive lead is longer.
• Secondly, where the negative lead enters the body of the LED, there is a flat edge to the case of the LED.

If you happen to have an LED that has a flat side next to the longer lead, you should assume that the longer lead is positive.

Page last edited October 05, 2012

Text editor powered by tinymce.

Parts Resistors Related Guides Your browser does not support the video tag. This links to the guide Silicone Robo-Tentacle. Silicone Robo-Tentacle By Matthew Borgatti beginner Electronic Demon Costume By Phillip Burgess beginner RePaper eInk Development Board By Bill Earl beginner Circuit Playground Sound-Controlled Robot By Anne Barela beginner Adafruit 16-channel PWM/Servo Shield By lady ada beginner Your browser does not support the video tag. This links to the guide 1,500 NeoPixel LED Curtain with Raspberry Pi and Fadecandy. 1,500 NeoPixel LED Curtain with Raspberry Pi and... By Phillip Burgess intermediate Adafruit Ultimate GPS Logger Shield By lady ada intermediate DS1307 Real Time Clock Breakout Board Kit By Tyler Cooper intermediate Memories of an Arduino By Bill Earl beginner Nokia 5110/3310 Monochrome LCD By lady ada beginner Photocells By lady ada beginner Your browser does not support the video tag. This links to the guide Multi-tasking the Arduino - Part 1. Multi-tasking the Arduino - Part 1 By Bill Earl intermediate Analog Feedback Servos By Bill Earl beginner Arduino GPS Clock By Tony DiCola beginner Arduino Lesson 3. RGB LEDs By Simon Monk beginner

Create Wishlist

× Title Description Close Search Search

Categories