LED circuits

Make sure you understand

• Forward Voltage and Current

A nice intro tutorial to understanding the calculations and principles of basic LED wiring arrangements. http://www.ladyada.net/learn/arduino/LEDs.html

More advanced - learn about use of transistors and constant current circuits. http://www.pcbheaven.com/userpages/LED_driving_and_controlling_methods/?topic=presentation

Things You Should Not Do With LEDs

• Connect directly to battery
• Connect to a power source without a resistor (or a constant current driver)
• Connect to an Arduino pin without a resistor
• Connect in parallel without resistors
• Think that you don’t have to limit current because you’re using PWM