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I bought some 200mW, 850nm IR LED's Answered

Picture of

I got them for a project and have been testing with them. So far I haven't been able make them product light with a AA battery. If anyone know what i can do to try to fix this please comment.
Thanks

PS. I was using a digital camera to check if it was emitting light.

Tags:led

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rickharris (author)2011-03-29

1, what is their specification? They will have a specific forward voltage required to drive them

2. You will/may need a resistor to limit te current flow.

As per this site http://led.linear1.org/1led.wiz

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frollard (author)rickharris2011-03-29

+1. 200mA seems like a lot of draw for a single 5mm led (per the picture). If those are 10mm leds, then 200 is acceptable but probably more than the standard 1.2v for an IR led.

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rickharris (author)frollard2011-03-29

his question actually says 200mW (S)He may have got that wrong though

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signposts (author)2011-03-30

Thanks everyone i think i have it working now. :D

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frollard (author)2011-03-29

Agreed. Definitely depends on the purpose of the led - the human eye detects most light sources as 'the same' after a brief adjustment from our iris... So yes, it can really help to run leds a lot dimmer than spec for a multitude of reasons. When it comes to needing an actual amount of light for a process or safety - go with spec :)

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ARJOON (author)2011-03-29

NICE. characteristic curve, lol, like in school atp

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