LEDs are tiny lights that can glow very bright but use very low amounts of electricity. They do not get hot like typical light bulbs. Perfect for DIY projects!
Remember to match the positive side (the long leg) to the positive side of the battery. LE’s will only light up when electricity is flowing in one direction. I call this LED a Ballerina LED because it has long legs that can twist into dancer poses. In industry it is referred to as a “through hole LED” because the legs go through holes in the circuit board.
Choosing LED’s for your project
Many LEDs look like this one, but they are not all alike. They operate at different voltage levels, so some won’t light up unless hooked up to a 9-volt battery, which would be a little chunky when added to your scarf or poster. In addition, you generally can’t combine Ballerina LED’s of different colors without adding resistors, because some of the LEDs will be dimmer or won’t light up at all when paired with other colors that require different amounts of voltage.
I have pulled together a selection of Ballerina LEDs that work with 3-volt batteries and don’t require a resistor (there is a little resistance in the conductive tape or thread). If you’re shopping elsewhere, here are some tips:
Minimum voltage: Look for LEDs that have a “minimum voltage” of 3.0 volts or lower–otherwise they won’t light up. (I’ve found that LED’s with a minimum voltage as high as 3.2 volts usually work.)
Forward voltage 2.7 volts or higher. Look for a “forward voltage” (the electricity flowing away from the LED) of about 2.7 to 3 volts or higher. This helps to avoid using up the battery or overheating it. It also means that all of your LED’s are close enough in voltage to allow you to combine different colors.
Check back soon for the Dragonfly LEDs that I invented with a printed circuit board company called Twisted Traces. They are designed specifically for use with conductive tape and threadey and they have resistors built in so that you can combine colors. (Thanks to Brian at Twisted Traces and my buddies at Workshop 88 for teaching me about LEDs and resistors!)