Alright, I bought a 3W 1.6v IR LED to make a night vision flashlight (because all digital cameras can see IR to some degree, depending on their filters), thinking I could power it just like I have all my other super bright flash lights, by hooking it up to a battery and a potentiometer in series. And I tried a NiMH AA and an alkaline, and they both supplied only around 30-60mA, but if my basic understanding of electronics is correct, 3W @ 1.6v = 2 amps, not 30-60mA.
So someone helpfully explained to me that this is because high power LEDs actually need driver circuits, to regulate the current when the voltage changes. And apparently the LM317T is one such regulator I have lying around.
Could someone please explain to me how I could use this to power my LED with a suitable high current wall wart (I have a 5v, 2A lying around, I know it won't be able to supply the LED with its max 2A after the voltage buck, and the LM317T's max current is 1.5A without a heatsink, but anything is better than 60ma)? I have found many guides on how to use it to power 2.5-3.5v white LEDs, but not 1.5v IR LEDs. I'm confused as to what vAdj resistor I am supposed to use, and if I need two or one, some schematics I've seen only use 1 while others use 2.
So someone helpfully explained to me that this is because high power LEDs actually need driver circuits, to regulate the current when the voltage changes. And apparently the LM317T is one such regulator I have lying around.
Could someone please explain to me how I could use this to power my LED with a suitable high current wall wart (I have a 5v, 2A lying around, I know it won't be able to supply the LED with its max 2A after the voltage buck, and the LM317T's max current is 1.5A without a heatsink, but anything is better than 60ma)? I have found many guides on how to use it to power 2.5-3.5v white LEDs, but not 1.5v IR LEDs. I'm confused as to what vAdj resistor I am supposed to use, and if I need two or one, some schematics I've seen only use 1 while others use 2.
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