Wiring LED Lighting

How can you wire up LED lighting? There are some precautions, in order to ensure long life of your bulbs, but it's easy, and they don't consume a lot of juice.

Why do you need a resistor with an LED? The short answer: to limit the current in the LED to a safe value.

The long answer: LEDs are semiconductors, diodes in particular. The current flowing in an LED is an exponential function of voltage across the LED. The important part about that for you is that a small change in voltage can produce a huge change in current. That is the most important concept of this article. Resistors aren’t like that. The current and voltage in a resistor are linearly related. That means that a change in voltage will produce a proportional change in current. Current versus voltage is a straight line for a resistor, but not at all for an LED. -More-

A good calculator for determining the size resistor needed for series/parallel strings of LED's can be found here. If using White LED's (3 in series) with a operating voltage of 3.8v, and a current of 20ma each, and a 13.8vdc supply, we want a resistor of 150 Ohm, 1/8 Watt.

These series strings of 3 LED's and one 150 ohm resistor can be wired in parallel.

Check out these Mega Bright white LED's.