Which MadMax for 1AA alkaline?

[JSWrightOC]

I'm going to get a famous Rothrandir M^3 (MiniMiniMag) host and put a MadMax in it. The primary power source will be Alkaline AAs, both used (to burn them up) and new...after that, NiMH cells. Extreme brightness is not a requirement, something that provides decent runtime and can suck alkalines dry. Can someone please help me...which MadMax?

 

[shiftd]

MM WO, of course
if brightness is not that important, then maybe you can get the MM adj, so you can adjust the trimpot to give you decent brightness just enough for your need.

 

[JSWrightOC]

My only concern is the low yield and flakiness of the adjustables. I read in the huge long thread "Long runtime madmax" about this...and inferred from the text that there was a an optimal MM to use.

 

[AilSnail]

I don't know that the mm+ will be brighter on 1xaa, but maybe.

Most importantly, get a low Vf luxeon.

 

[shiftd]

i think the optimal MM is the MM WO that was preset to the highest brightness. again, depending on your need, you might be better off with an adjustable so you can adjust the output. It is a heck to adjust it at first, but once you find the best spot, then no need to adjust it more.

 

[Bullzeyebill]

MM+ is brighter than MM, at least mine is, and R2H MM+WO is brighter yet. See Roy's run time with mmm, with MM+Q3L, in Reviews, to get an idea.

Bill

Also, good runtime.

 

[vcal]

[ QUOTE ]
JSWrightOC said:I'm going to get a famous Rothrandir M^3 (MiniMiniMag) host and put a MadMax in it. The primary power source will be Alkaline AAs, both used (to burn them up) and new...after that, NiMH cells. Extreme brightness is not a requirement, something that provides decent runtime and can suck alkalines dry. Can someone please help me...which MadMax?

[/ QUOTE ]
MadMax+...you're gonna love it. /ubbthreads/images/graemlins/smile.gif

About 60% bright as running 2 cells, but very adequately bright until the alkaline get really really low....which in turn brings out the efficiency in the performance of the Luxeon itself.

Avg. 75% of new cell brightness:

Estimated runtime with MMX+ single cell, and new regular alkaline, about 1 hour.

-with Photo oxy/alkaline (ZR6) (higher voltage-like L91 Lithium) is 25% brighter than regular alkaline-about 1.5 hours.

-with L91 AA Lithium same brightness as Photo oxy/alkaline-ZR6 about 2 hours.

-with 2100mAh NiMH AA, Very slightly dimmer than standard alkaline but with more consistent brightness than using a standard alkaline-about 1 hour plus..

p.s.-the ZR6 Oxy/Alkies are available at Savon/Osco at 4 cells for $4.00
Have fun!...... /ubbthreads/images/graemlins/cool.gif

 

[Doug S]

Since your primarily source will be a single alkaline AA, wait and get one of the special run MMs that Wayne is doing using the MAX1675 IC. Wayne is calling this the low power MM but using a single alkaline AA it will outperform the other MMs in both brightness and runtime. The runtime advantage over the other MMs will be large. This is due to the particular current limited switching topology that the MMs use. The standard MMs limit at 1A and the low power MM at 0.5A. At a 1A limit, much of the battery energy is disapated in the battery and circuit, not the LED. Note, this explanation applies to use of a single alkaline cell.

 

[JSWrightOC]

Doug S:

Thanks you! This is exactly what I am looking for - I thought I was going crazy trying to find it on his site. Any estimation when it might come out?

 

[shiftd]

Doug, that is a good news. So any other spec that you can give us regarding this? i mean, if it is optimized for max runtime, how good is the output? and how would it compare to the original MM? Would the lux be overdriven like the original when we use fresh AA alkaline?

 

[Doug S]

[ QUOTE ]
shiftd said:
Doug, that is a good news. So any other spec that you can give us regarding this? i mean, if it is optimized for max runtime, how good is the output? and how would it compare to the original MM? Would the lux be overdriven like the original when we use fresh AA alkaline?



[/ QUOTE ]

I really doubt that on a single fresh alkaline the original MM will overdrive a white luxeon though it might for a red, red-orange, or amber. I would estimate that for a white you will be in the 250-300mA range with the MM and a bit lower on the "low power" MM. The original MM will best the low power MM for perhaps the first 10-20% of discharge but averaged over the total discharge the low power version will be the superior performer. BTW, on NiCd or NiMh, the origninal MM will be the brighter for the total runtime.

 

[Dan C]

Just the kind of information I've been looking for Doug, thanks. You just answered many of my questions. I too am anxiously awaiting the new MM for low power apps!

Dan C

 

[BentHeadTX]

Thanks for asking and answering the question,
I will go for the low power MM and slap my red LS on the puppy. The final concept will be a Stoplight single AA with a minimag reflector. Now...the wait.

 

[AilSnail]

Will the low power MM be more efficient than the regular MM and MM+ if these are turned down to match lpMM?

Will MMregular be more eff. than MM+ if MM+ is turned down to match MMregular?

 

[Doug S]

[ QUOTE ]
AilSnail said:
Will the low power MM be more efficient than the regular MM and MM+ if these are turned down to match lpMM?



[/ QUOTE ]

Yes. The lower current limit of the low power MM will result in lower I^2R losses.

[ QUOTE ]
AilSnail said:
Will MMregular be more eff. than MM+ if MM+ is turned down to match MMregular?

[/ QUOTE ]

I don't know. The two use different inductors and I do not know their specs. The difference is likely small.

 

[dat2zip]

I think the testing I did last year showed that at 3V the lite was around 94% efficient and dropped to 89% efficiency around 1.2V or so.

The Plus on the other hand starts around 90% and drops to 84% efficiency at 1.2V.

(That's off the top of my head, which forgets things quickly...)

 

[AilSnail]

Edit: sorry I got confused on the new terminology.

Doug, thanks, I understand, but not how. /ubbthreads/images/graemlins/smile.gif

Great data, Zip. It's always more fun to choose when there are several things to weigh.