Driver for 2D alkalines for about 500-600mA?

wquiles

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I have a project in which I want to retrofit a 2D M*g body with one a multi-LED (5mm) head that will host about 30 of them or so. I need about 500-600mA from 2 D alkalines but I want to drive the LED's until the D cells are killed, gone. I want to extract as much juice from these 2D's as possible.

What would be a good driver for this?

Will
 
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wquiles said:
I have a project in which I want to retrofit a 2D M*g body with one a multi-LED (5mm) head that will host about 30 of them or so. I need about 500-600mA from 2 D alkalines but I want to drive the LED's until the D cells are killed, gone. I want to extract as much juice from these 2D's as possible.

What would be a good driver for this?

Will

Any kind of boost converter should work.
 

wquiles

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Yep. I have tons of these D Alkalines and I want to have a flood-like beam for emergencies so when it starts diming considerably, then it is time to trow these cells away and put new ones in :)

Will
 

PhotonAddict

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I think the Madmax from the Shoppe would do the job. For approx. 600mA to the led you would need the MM+. Draws approx. 1A from the batteries as I recall.
 

HarryN

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Will, if you want the best drain from the cells, it is ideal to use a buck converter and enough cells to stay above Vf, even after they are almost dead. I know that your preference is 2 D.

Would you consider putting 2 Li enhanced D cells in that light for very long run time ? (yes, I know that is $ 30 worth of cells.)
 

IsaacHayes

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Constant current such as BB500 wouldn't be good for draining them completly. Maybe the NG500 would work, as it goes into a safe mode that is like moon mode, but more efficient I've heard.

If you go for a voltage boost circuit, it may not be exactly flat output as long as a constant current would be, but it will drain the cells down until they are toast. Something like a MadMax would be ideal. There are variations MM+, MM+ WO, not sure which is the best in this case...

For draining alkalines in emergencys and getting light out of "almost dead" cells a unregulated voltage boost circuit is what you need. A madmax, or even a micropuck HO or 2 micropucks in parallel should be good.
 

wquiles

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Cool - it looks like the Madmax is it!

As I have never used one before, how do you set and/or limit the current in these?

Will
 

PhotonAddict

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As far as I know the MM Lite and MM+ from the Shoppe are "wide open" - they will draw approx. 500mA and 1A respectively from the batteries regardless of the load so that work out to approx. 350mA and 700mA to the leds depending on the forward voltage of the led.

They are not truly current regulated like the Badboy converters so the current delivered to your leds would depend on how many you have connected and their forward voltage. You can use some small resistors as well to control things. Some use a small resistor with each led to account for the slight variation in Vf (I'm assuming you are connecting them in parallel).

btw: if you considering the micropuck, here is useful link with application notes that will help get you started:
http://www.leddynamics.com/LuxDrive/micropuck.php

Hope that helps.
 

vortechs

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wquiles said:
The micropuck looks great. I went ahead and ordered two of the "high" power version units to test in my setup - thanks ;)

Will

Hi Will,

Where did you order the MicroPuck (2009-HI) converters from? Did they have good prices and reasonable service?

How did the MicroPuck work in your application?
 

ktronik

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Dude,

arcamania had a heap of $5 1/2 cell boost drives... very small..

I got heaps...very happy...

I get 500-600ma depening on the cells...

I made a aray like the one you talk about...using 6/ 16L 8mm white...works well..

enjoy

Ktronik
 

vortechs

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ktronik said:
arcamania had a heap of $5 1/2 cell boost drives... very small..

What are the dimensions of the arcmania $5 boost drive (diameter and height)? I am trying to determine if they would fit in a JIL-CR2 1.3W, in place of the tiny MicroPuck.

Are the $5 arcmania boost drives the ones that LITEmania is currently selling?

Thanks!
 
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