Lumileds 5W Luxeon Announced

[Klaus]

dat2tzip - how do you calculate 3.2W for a current 1W Luxeon ?

The most I heard off was driving it around 700ma - but this would need to be at 4.5V to get you 3.2W - or are you just using 4.5V in your math - this no-load voltage of 3 cells isn´t too accurate I think - the voltage under load will be quite lower and your Wattage too though.

Klaus

 

[LED-FX]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR> wasn't quite clear on exactly how they work from reading their website, though. <HR></BLOCKQUOTE>

Peltier`s are fascinating devices but not the worlds most efficient way of doing things, more info:
http://www.peltier-info.com/

Think liquid cooling may not be such a pie in the sky idea,Fluorinert was the clear liquid used to cool Cray supercomputers.Dont think it has any enviromentally friendly properties though :-(

De-inonised water would work though, water itself isn`t conductive, its dissolved minerals that make it conductive.

This coupled with a piezo-electric pump......hmmm must go got to dash to the patent office :-)

Adam

 

[Alchemist]

[No message]

 

[dat2zip]

Klaus,

I think the Mag light conversion can peak up to around an 1A. I was somewhat conservative and used 4.3V and 750mA.

I've run the LS up to 1A with a good heat sink.

In the beginning with my first three LS from ARC I nearly fried them all. I had them hooked up to three NiMH batteries and no series resistor. They were running 750-800mA and I was getting a run time of approximately 45 minutes and I did not have a heat sink attached. I burned my fingers a couple of times.

Geez, I'm sooo lucky to not have cooked one. But, they sure lit up like a flood lamp! I used them mostly to take walks. Good thing it was cold outside at the time.

 

[Jonathan]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by LED-FX:

Think liquid cooling may not be such a pie in the sky idea,Fluorinert was the clear liquid used to cool Cray supercomputers.Dont think it has any enviromentally friendly properties though :-(

Adam<HR></BLOCKQUOTE>

Fluorinert is not all that bad environmentally. It is _very_ stable, which means that it pretty much doesn't react with anything, and is thus has very low toxicity. It doesn't contain chlorine, bromine, or iodine, and so doesn't harm the ozone layer. It isn't known to be carcinogenic or mutagenic, which means that if they've done any testing at all, it's carcinogenic or mutagenic effects much be rather low order. It is a greenhouse gas, so you don't want it to evaporate. Also, because it is so stable, if it does get spilled, it will stick around for a long time.

I've never used the stuff, but my guess is that if by using it the LEDs are more efficient and less electricity used, then I would bet that using the stuff would mean a net environmental win.

-Jon

 

[Jonathan]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by alchemist:
How delicate are the luxeon stars. [...]Also (bearing in mind I know nothing about leds) why are they so sensitve to high temperature in the first place?

Alan.<HR></BLOCKQUOTE>

As far as semiconductor devices go (computer chips, transistors, etc.) Luxeons are not particularly sensitive to high temperatures...it is just that 'high temperature' for a semiconductor device is low compared to the 'high temperature' found in most other light sources.

The maximum rated junction temperature for a Luxeon is 125°C. The filament temperature of a light bulb is something > 3000°C. Luxeons have a lot of heat which must be carried away (as much as a similarly rated light bulb), but the heat must be carried away keeping the junction below max temperature.

LEDs also tend to be more efficient at lower temperatures, so even if you are not approaching the maximum allowable junction temperature, you want to keep the junction as cool as possible to get the most light out of it. Most other light sources get more efficient as they get hotter.

Luxeons do use a number of tricks to both improve heat conduction and to improve maximum junction temperature. Luxeons can deal with heat better than any other LEDs, but LEDs simply cannot be allowed to get hot.

-Jon

 

[Klaus]

Just off the phones with Lumiled

The current release date for the new WHITE 5W and also the new white HD labertian (30lu/W?) parts is July (this year

)

Klaus

 

[remuen]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Klaus:
Just off the phones with Lumiled

The current release date for the new WHITE 5W and also the new white HD labertian (30lu/W?) parts is July (this year

)

Klaus<HR></BLOCKQUOTE>

If you believe it I do it too

 

[JollyRoger]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by dat2zip:
Klaus,


I've run the LS up to 1A with a good heat sink.

In the beginning with my first three LS from ARC I nearly fried them all. I had them hooked up to three NiMH batteries and no series resistor. They were running 750-800mA and I was getting a run time of approximately 45 minutes and I did not have a heat sink attached. I burned my fingers a couple of times.

Geez, I'm sooo lucky to not have cooked one. But, they sure lit up like a flood lamp! I used them mostly to take walks. Good thing it was cold outside at the time.<HR></BLOCKQUOTE>


Sheesh, Wayne! You're definitely living on the edge!!!!

And to think, I've been feeling guilty all this time for driving my Luxeon with 3AA nimh and no resistor....for fear that I was doing long-term damage...

 

[L.E.D.]

 

[carl]

I can never find anything in the literature about side emitters which would help focus a longer-reach light in a reflector. Does anyone know if the new bulbs will be available in side-emitter configuration?

 

[**DONOTDELETE**]

The new Luxeon 5 Watt is available in Cyan, Green, Blue and Royal Blue from mid May. White due for release early to mid july. Side LED also available in 5 watt package from JULY.

 

[dat2zip]

It's almost mid May by my calculations. Any new information?

 

[Tritium]

Spammer REPORTED!!
That was fast action removal.
Thanks


Thurmond