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ArcticMyst Security by Avery

Stacking drivers using led flashlights as hosts.

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I wonder if stacking drivers in series is ok. I want to use a high power variable led flashlight driver up to 8.4v with strobe and sos and charging functions remove its led and stack the driver for a 2w laser replacing the led. Is this ok? Seems to me with my mechanic knowledge that it would work but I am not adept at electronics. Any help would be greatly appreciated!

Flashlight host:
Online Shop Flashlight Torch 2000LM CREE XM-L T6 LED 18650 Lanps Waterproof Lantern + Battery + Charger|Aliexpress Mobile

Attached are the specs for flashlight.

Any ideas on a cool efficient heatsink for this?
 
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I've run drivers in parallel for LED's by isolating them from one another with a blocking diode and I know other members have done the same thing to double the output current, but I don't know if they always use a blocking diode or not, which designs require it or not.
 
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That DTR module already has a driver in it, so I'm somewhat confused. If you mean will the driver from the flashlight which produces 8.4 VDC work in series with the DTR module which has its own internal constant current driver too, I would think so, as long as the flashlight driver will supply enough current for the DTR driver, I don't see why not. Maybe this isn't what you are asking. I tried loading the link to the flashlight, but it didn't load properly for me, most of the info on that page is missing for me.

Do you know what current that flashlight needs for the LED's it uses? Beware though, many flashlights like that do not run at the full current the LED is capable of taking, so you can't judge its drivers output current by the LED they use in it. You would be lucky to find someone who is familiar with that particular flashlight to be able to answer much about it. All you have to do is determine the current and voltage needed by the DTR module and the voltage and current the flashlight driver is capable of putting out, but I see no reason to even use the flashlights driver, if its batteries inside do not supply more than the voltage the DTR module will allow.

Does that flashlight use two 18650 batteries? I think I see those in the photograph, if so, you shouldn't have more than 8.4 VDC from those batteries, less than that as they drain from use.
 
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You would under no circumstances power that x-drive built into that module with another driver, it will not work properly. You would use a battery contact board to power the x-drive directly from 2 Li-Ion batteries.

Alan
 
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I don't see a reason to do that myself, but if the current drawn from it by the DTR module with its own regulator does not meet or exceed its capability, why wouldn't it work? I wouldn't do it anyway, no need and increased losses without reason. However, I can see this problem; if the DTR module hits the current limit of the flashlights driver and wants more, now you have a problem.
 
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A constant current driver needs a voltage source, not a constant current source, it needs to draw whatever current it will and needs a voltage within a certain range, the driver will vary the voltage when needed to keep the current the same. I would like to see someone try this and put a scope on it to see what's happening, I don't believe it would work properly.

Alan
 
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I was thinking the voltage output would remain high from the first driver, as long as the constant current limit didn't kick in. Maybe I have a bad concept of how it works.
 
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Well I could be wrong but it seems like it shouldn't work properly. One thing worth mentioning for the OP if he didn't want to bother with replacing the LED driver in the flashlight with the battery contact board, you can often remove all the parts from the driver and reuse it as a battery contact board. Probably more work than just replacing it though.

Alan
 
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Ok I'm going to have to wait and get this flashlight in the mail to run some tests on it. I should probably build a test board? And or get some specs for the driver I'm using. I'm wanting the charging , 3 stage light strength adjustment(wich now that I'm thinking might just starve and then max the laser driver), strobe, and SOS capabilities of the power board in the flashlight to work with the laser. The untested 8.4v from a single 3.7v batt I believe is being prouduced by a step up board built into the flashlight. It is 1600lumens. I will be waiting about 2 more weeks for arrival.
 
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Thanks everyone! Looks like I'll prob just leave the flashlight a flashlight and or put a 405nm led in it. If I can find one strong enough. Also find a more proper host. Anyone know of one that will work with this module that has a nice heatsink and maybe even accepts kelidascope tips?
 
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I looked up the specs for a Cree XM-L LED and the voltage they run at is close to 3 volts, the current from 1500-3000 ma from 2.9 to 3.35 VDC. I couldn't find specs for a "T6" specifically, maybe I'm not looking at the right device.

Here's a URL to a spec sheet: http://www.cree.com/sitecore module...inning/XLampXML_EZW.pdf#search="CREE XM-L T6"

Did you mean 405nm LED or laser? If you haven't seen the output of a 405nm laser diode yet? Although they are very weak looking to the eye, they can burn very quickly, I believe this is one of the most dangerous lasers out there.
 
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The only website with specs detailed at all for this Cree model are on a app powered by wish called GEEK . I also wondered if the board inside this fl could be modified to power a laser diode by itself.
 
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I don't think the board inside that particular flashlight is suitable for powering a laser diode, the voltage is just too low unless IR, and then too high. Perhaps there are some boost drivers which could work off of 3 VDC, but why do that when you could just use the voltage directly from the battery if you already had a driver built into the module. Anyway, good luck.
 
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And I meant led. I am getting another 405nm soon this guy has 700mw ones for sale that ships in days. I am mounting that one into a host I also got from geek
 




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