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How do I use a high power LED in a a low power circuit? Answered

I want to replace a remote control's low power IR LED  to a high power IR LED, or preferably an IR laser diode.
Obviously replacing the original LED with the high power one won't do it.

What is:
1) The easiest way to make it work?
2)The best way to make it work?

If at all possible, link to a diagram or an instructable, that would be super!
Thanks :)

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steveastrouk
steveastrouk

Best Answer 8 years ago

Add a separate transistor to drive the LED

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Morgantao
Morgantao

Answer 8 years ago

how would I connect the transistor?
Which leads of the transistor would be connected to what?

I've found a photocoupler. Would it work if I use it instead of the original LED and connect the other end instead of a switch on my laser diode?

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steveastrouk
steveastrouk

Answer 8 years ago

You need to be more specific. How much current and voltage does the diode need. If you're driving laser diodes they are VERY sensitive to the supply. One false move and (poof) no diode.

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Morgantao
Morgantao

Answer 8 years ago

If I'll use a laser diode, it will have it's own driver and power supply.
The remote operates on 3v, so in both cases (Either I use transistor or a photocoupler), I need another power supply to run the laser (Or high power LED).
Or am I completely off?

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steveastrouk
steveastrouk

Answer 8 years ago

If the driver has its own gate input, you're good

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jduffy54
jduffy54

Answer 8 years ago

A) I'd use the high power LED, it will have WAY more than enough power, and won't be as finicky with direction. I would use a TIP120 transistor (Radioshack carries them), with the base to the original LED's output (whichever one goes to a chip), through a resistor. the collector to the LED negative, the LED positive to power positive (through a resistor, if needed), and the emitter of the transistor to ground. (TIP120 pinout is base on the left, collector in the middle, emitter on the right.).

This should work for really any LED, but make sure that the LED will run on the power supply without burning out first.

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Morgantao
Morgantao

Answer 8 years ago

I kinda got lost :)
LED vs old LED is confusing.
If you can provide a simple schematic it would be great.

Better yet, I'll try to be less vague about what I'm trying to do.
I want to make an extreme long distance remote. By extreme long distance I mean hundreds of yards. That's why a laser diode seems to be the right thing - It's high power and very directional (Cheap old 4.5v red laser pen I have is bright enough over more than a mile, and the beam divergence was not too shabby).
Assuming I have an IR laser pointer, How would I do that?
I would really love to see specific part numbers, as TIP120, and resistor values.
Thanks for all the help guys, you're great!