Lets get right to it:
Each of the steps do the same thing. Step 1 is the simplest and we go downhill from there.
No mater what way you choose you must first know these three things:
- Supply voltage This is how much power you're putting into the circuit. Batteries and wall warts will have the output voltage printed on them somewhere. If you're using multiple batteries*, add the voltage together.
- LED Voltage Sometimes "Forward Voltage" but usually just abbreviated "V".
- LED Current Sometimes "Forward Current". This is listed in milliamps or "mA".
Red LED: 2V 15mA
Green LED: 2.1V 20mA
Blue LED: 3.2V 25mA
While LED: 3.2V 25mA
Okay, lets get started!
* Batteries in series.
Introduction photo credits:
LED photo by Luisanto.
Resistor photo by oskay.
Step 1: The Web Way
Just click on one and enter the info from the previous step and you're set! You only need to go to one.
The LED Center (For single LEDs)
The LED Center (For arrays of LEDs)
LED Calculator.net (For single or arrays of LEDs)
LED Calculator.com (For single or arrays of LEDs)
Step 2: The Retro Way
PDF, assembly and usage instructions are all on the page linked above.
It's pretty nifty and ends up being about business card size so you can keep one in that box with the rest of your LEDs.