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By RSHunter
#205719
Recently ordered a 10mm super bright LED, and a 2xAA battery holder thinking that was all I would need.. and of course I was incorrect. I am looking for someone to tell what else I need to buy (wires, connectors, resistors etc) in order to set up a small circuit.
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By TS-Chris
#205727
Hi Ryan, and thanks for posting.

You're going to need a resistor to prevent the LED from drawing too much current and burning out. We have a tutorial that shows what size resistor to use for a given LED and voltage but you're safe using a 330 ohm resistor if you don't want to do the calculations. Our part number PRT-14490 would work fine for your project and the tutorial shows how to connect everything.

The only issue I see that might be a problem for you is that the LEDs you're using have a forward voltage between 3.0 and 3.4 volts any you're using two AA batteries that are 1.5 volts each. You're probably only going to be able to light up the LEDs with brand new batteries and as the batteries begin to run down, the LEDs won't light anymore because your batteries will be at a lower voltage than the LEDs need to work. I'd recommend using a 4AA battery holder like PRT-00552 as that would give you plenty of voltage so you don't need to worry about the batteries being brand new. (You could also add a second 2AA battery holder for 4 total batteries, but it might be easier to use the 4AA holder, and you'd have your 2AA holder for another project!)

I recommend you check out the tutorial as well, but the diagram below shows how you could put this together.
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