8mm LED's in Arc AA?

8mm LED\'s in Arc AA?

djpark's mod of an Arc AAA using ISP's 8mm white, four dice emitter -

http://www.candlepowerforums.com/ubbthreads/showflat.php?Cat=&Board=UBB14&Number=462940&page=0&view=collapsed&sb=5&o=7&fpart=1

I think this (or similar) LED would be a fantastic alternative to the 5mm currently used in the Arc AA, helping to differentiate the AA from the AAA - as well as the competition - by upping the lumen output to somewhere between that of the 5mm's and the LS emitters. Output more relative to body size.

By the looks of it, this ISP 8mm has a nice, smooth white, task-friendly beam, too.

Epoxy-packaged LED's have a durability advantage over LS's in simple, exposed applications like the AA and AAA Arc's, as well as the advantage of no required reflector/lens/collimator, as the epoxy package itself does the collimating.

I also doubt that heat-sinking would be much of an issue (as long as the emitter isn't severely overdriven), as it can be with the higher output Luxeons.

Ideal for the Arc AA, then! /ubbthreads/images/graemlins/thumbsup.gif

My Arc AA is one of my favorite lights, but as a flashaholic, the wish for a little more output seems to be a typical symptom of the disease, right /ubbthreads/images/graemlins/sick.gif ?

I decided to post my thoughts on this as I don't have the time/tools/ability/eyesight/etc.. to do such a mod to my own AA, and I'm hoping you'll all jump in with support of the idea - giving poor Mr. Gransee no choice but to make 'em for us /ubbthreads/images/graemlins/grin.gif !!

So... what say ye, CPF'rs/Arc fans - yay or nay?? /ubbthreads/images/graemlins/thinking.gif

Bob

Re: 8mm LED\'s in Arc AA?

I thought that 8mm AAA mod was really nice too. I'm not too keen on the way that the AA and AAA led's are so overdriven. I've been lobbying for a while for Luxeon versions of those lights for people wanting more brightness. The 8mm led with 4 dice in the package is an interesting alternative.

Re: 8mm LED\'s in Arc AA?

paulr -
Yes - in viewing the beamshot photos djpark posted of the underdriven 8mm (80ma?) vs. the Arc AAA P (overdriven), and considering the increased lumen efficiency of LED's at lower drives (or at least the diminishing returns when overdriven) - the 8mm's output is rather impressive for running at about 170% current draw vs. the ArcP. Should allow for an easier LED life, I'd think.

Another advantage!!

Re: 8mm LED\'s in Arc AA?

Looking at ARCAA with Infinity Ultra near similiar amount of light output, I believe ARCAA is driven at around 60ma or so because both my dissected Ultras are at 66ma when the cell is fresh.

That's at least a 100% overdriven 5mm Nichia if you ask me.

Say the absolute max current for a 8mm LED is 80?/100ma? that means we'll have an underdriven 8mm LED if Peter uses the stock ARCAA circuit board.

Judging Peter@ARC by person, I think this is unlikely. I haven't seen many of his products underdriven. The underdriven is the famous 2.5W LS3 and the recent release ARC4 series(which is also heavily boosted if commanded). Like many others(mod to max amps) in this forum, I believe he drives a honda with an extra tacho, rpm and psi gauge. Ok I am babber too much... /ubbthreads/images/graemlins/grin.gif

I don't know if the current ARCAAA/AA boost circuit can be tweaked to output of say 150ma, it would be good because
Peter can quickly get this out without much development cost. That is if he want's to make a 8mm.

Another thing is that the AA battery should have enough juice compared to it's AAA elder brother.

I am looking forward to own one though /ubbthreads/images/graemlins/popcorn.gif

Vince.

Re: 8mm LED\'s in Arc AA?

Condider my support given /ubbthreads/images/graemlins/thumbsup.gif

Re: 8mm LED\'s in Arc AA?

i would buy at least 2, now.

Re: 8mm LED\'s in Arc AA?

I think it's worth looking into. Not much extra work for a nice step up inbetween. AAA-5mm, AA-8mm, LS-LS! Nice.
But then again a AAA+ with 8mm would be cool too. But if the AA is staying around it would probably fit better into the scheme of things.

Re: 8mm LED\'s in Arc AA?

koala -

Max current spec on this LED appears to be 100ma. 2x that (200ma) would be a comparable overdrive according to your 5mm observations (ouch!). I'd guess 150ma would be a more realistic, conservative overdrive (is there really such a thing?).

Certainly would be a bonus if the current AAA/AA circuit design could safely be tweaked to handle those loads.

But regardless of whether the design would end up being over or underdriven - as far as I can glean from the posted info djpark provided, it simply appears that a useful, noticable output increase over even a much over-worked 5mm would result - and it's apparently UNDERdriven. All good, is how I see it. A great "in-between" solution.

Badbeams -

Thanks! If enough of us snowflakes collect, maybe we'll have a SNOWBALL!! /ubbthreads/images/graemlins/naughty.gif

Bob

Re: 8mm LED\'s in Arc AA?

[ QUOTE ]
artar said:
i would buy at least 2, now.

[/ QUOTE ]

Me too!! /ubbthreads/images/graemlins/grin.gif

Re: 8mm LED\'s in Arc AA?

I looked at that LED but haven't yet found a good place to buy them. Busy getting read for the SS and all...

Peter

Re: 8mm LED\'s in Arc AA?

i stuffed one into a pr base with a 3.9 ohm resistor.
about 225 ma on 3 alks.the pr base and metal bulb receptical act as a heatsink and is holding up just fine.
i used a bench supply to enforce full voltage for a 1 week test.no loss of output.

[ QUOTE ]
Moat5606 said:
koala -

Max current spec on this LED appears to be 100ma. 2x that (200ma) would be a comparable overdrive according to your 5mm observations (ouch!). I'd guess 150ma would be a more realistic, conservative overdrive (is there really such a thing?).

Certainly would be a bonus if the current AAA/AA circuit design could safely be tweaked to handle those loads.

But regardless of whether the design would end up being over or underdriven - as far as I can glean from the posted info djpark provided, it simply appears that a useful, noticable output increase over even a much over-worked 5mm would result - and it's apparently UNDERdriven. All good, is how I see it. A great "in-between" solution.

Badbeams -

Thanks! If enough of us snowflakes collect, maybe we'll have a SNOWBALL!! /ubbthreads/images/graemlins/naughty.gif

Bob



[/ QUOTE ]

Re: 8mm LED\'s in Arc AA?

[ QUOTE ]
Gransee said:
I looked at that LED but haven't yet found a good place to buy them. Busy getting read for the SS and all...

Peter

[/ QUOTE ]

Hello, Peter -

Do you mean in large production quantities, or just a small test batch? If a test batch, I'd be more than happy to hunt down a handful to send your way - just let me know how many.

Snakebite -

Wow - seemingly durable as well. Cool!

If you've got a minute... What are your impressions of the output/color/beam? Satisfactory for an application like what's being discussed? Also - where'd you find 'em?

Thanks! /ubbthreads/images/graemlins/smile.gif

Bob

Re: 8mm LED\'s in Arc AA?

Count me in on one if they are made!
Love my Arc AA, great light but a bit more brightness would rock! Really don't understand why you would overdrive the crap out of the LED though... running it 100mA would give decent light, long life, no worries about sinking the heat and the battery life would be around 8 hours.
5mm AAA, 8mm AA and LS gives a nice spread in the range. CPF special 8mm AAA... oh yeah! /ubbthreads/images/graemlins/bowdown.gif /ubbthreads/images/graemlins/grin.gif

Re: 8mm LED\'s in Arc AA?

[ QUOTE ]
Gransee said:
I looked at that LED but haven't yet found a good place to buy them. Busy getting read for the SS and all...

Peter

[/ QUOTE ]

You can buy from the manufacturer directly.

http://isp.koreasme.com/index_e.html

8mm is not listed there, so send email to [email protected] to ask for price. Very nice person to communicate with!

They will send by EMS and it would take 1 week to reach you. Please try their 5mm white led, too.

-- DJP

Re: 8mm LED\'s in Arc AA?

Put me down for one if he makes it.

djpark,

How are their 5mm's? Are they as blue as the Nichia's? What about differences in beam profile?

Re: 8mm LED\'s in Arc AA?

[ QUOTE ]
Lux Luthor said:
djpark,

How are their 5mm's? Are they as blue as the Nichia's? What about differences in beam profile?

[/ QUOTE ]

I left some info in this thread .

You can also get the datasheet at http://djpark.astsb.info/cpf/5mm_white.pdf .

-- DJP

Re: 8mm LED\'s in Arc AA?

do i smell a group buy?
i will be ordering a bunch so maybe a gb would be a good idea?

Re: 8mm LED\'s in Arc AA?

There's a guy in Boston who's selling them for $3.00 each shipped (minimum order 2 pieces). A GB only sounds worthwhile if you want enough pieces that getting a better price is worth the trouble of the GB.

Re: 8mm LED\'s in Arc AA?

I think an ARC AA with 8mm LED would be a great addition to the ARC lineup.

Re: 8mm LED\'s in Arc AA?

Something hit my head, I remember first ARC LS-series uses two boost circuit in parallel to provide power to the Luxeon.

If two makes around 300ma(assuming) to the Luxeon, that means one can supply at least 150ma? I don't know how the circuit actually works but if it's really 150ma then I guess it's a perfect candidate for 8mm.

Vince.