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ArcticMyst Security by Avery

Multiple CREE led build?

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Jul 15, 2012
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After doing some researching and finding that CREE leds are EXTREMELY bright, I want to build a multiple CREE led flashlight. One of my current flashlights uses a CREE led and after searching the circuit board for quite some time, I have found 1 SMD resistor, and I can see 3 characters on the top of it, but can only make out the first 2 which is 24. so, if I were to build this multiple CREE led flashlight, what kind of circuitry would I be needing to create? I plan on getting some round circuit board from rad shack to base this off of.

I just ordered 4 of these suckers. What kind of battery power will you guys think I may need?

Original New CREE Q4 3W 300 Lumen LED Chip with 20mm White Star Base | eBay
 





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Read through DealExtreme a bit. Couldnt find much info on how to run 4 CREE leds togetger. What would be the best way to wire these? In parallel or series? I know that the small 9 led flashlights are run in parallel. I dont know how to equate what kind of power I will need either. The leds are 3-3.5vf each, and for the full lumen output they will need 1000ma each. Which equals out to 3 watts per led.

Bat+ +led- +led- +led- +led- -bat
Or
Bat+ +led- -bat
Bat+ +led- -bat
Bat+ +led- -bat
Bat+ +led- -bat
 
Joined
Sep 12, 2007
Messages
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Bat+ +led- +led- +led- +led- -bat
Or
Bat+ +led- -bat
Bat+ +led- -bat
Bat+ +led- -bat
Bat+ +led- -bat

Fd111.gif


Not sure if explicating or patronizing.

Series is inherently better because it ensures the same current flows through each component.

I know that the small 9 led flashlights are run in parallel.

They also cost 99 cents and last only a few hours.
 
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The reason I wrote it out that way was because I was demonstrating to my roomate the difference in parallel and series. So, Series would be the best, which means 12-14V supply at 1000mA, or 12-14V 3w. What would be the best way to get 12-14V from small batteries? I want this flashlight to be fairly compact, but I also want many hours of use from the batteries. looks like an A23 battery would work pretty nicely, but I dont know how long it would last.
 
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...... A driver regulates current for longevity. It needs a battery to work? I didnt know that the driver pulls electticity out of nothing to power my leds.
 
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Yeah, you might want to look into a multiple battery packs with them wired in parallel to provide a constant high power output while keeping it all operating in a safe range. Usually the heat is a bigger problem in those higher power units. More battery packs providing the power means less draw from each and less heating as a result. (Not taking the heat being produced by the LED elements into consideration !)
Multiple battery packs also means that you will get a longer time of usage.
The down side is determining just how much weight you want to have and how much space will be available for the end project.
Finding the balance between the variables is up to you and will make your solution, more than likely, very different from someone else's method of doing the same thing.

Have fun and don't forget to post some pictures of what you do.
:p
 
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Alroght. I did a little looking around and im thinking maybe 2 6v batteries or 4 3v batteries. The 4 3vs would need a long case, but 2 6vs would probably be about the same length as a 3 AAA battery pack. I may consider 2 12v batteries (a23) and running a resistor or a small pot to drop it down to 12v.
 
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Hell, just replace your car battery with a a23 while you're at it. It's 12V so it should work. :tired:
 

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CREE LED's and AAA's/a23's really don't belong in the same sentence lol.
 
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If I'm not too senile yet, I think there was a build thread here for something similar.
Someone built a LED "flashlight" that you could tan under and he gave lots of details about his choices for power and why. Try searching for "flashlight". Lots of threads that are useful come up.
 




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