CREE introduces 3 Watt LEDs

[NewBie]

http://ledsmagazine.com/articles/news/2/7/20?alert=1

Cree Lighting has released a new 3-watt XLamp 7090 high-power LED in a full range of colors.


XLamp 3 in white
At the same time, Cree announced its first design win for the white 3-watt XLamp.

Cree says that the white version of the new XLamp LED is the first 3-watt product to produce a maximum luminous flux of more than 90 lumens. The XLamp 3 7090 white LED achieves an average luminous flux of 85 lumens, well above the 65 lumens typical rating reported for existing 3-watt LEDs.

At the same time, Cree announced that its new white LED will be incorporated into Cyberlux's new RelyOn portable work and emergency light.

"Based on the new 3-watt XLamp LED, Cyberlux's new RelyOn http://www.ledsmagazine.com/press/9677 portable emergency light achieves more than 60 hours of operational spot and flood lighting," said Mark Schmidt, Cyberlux president and COO. "Cyberlux is developing a broad range of products based on Cree's XLamp LEDs for emergency, task and large scale lighting applications."

The powerful, solid-state semiconductor light head, powered by three Cree 3-watt XLamp(TM) 7090 high power white LEDs, provides over 250 lumens and may be focused as an intense spotlight beam or adjusted to generate a blanket of light similar to a table lamp. The intensity of the light can be adjusted for both the spotlight and floodlight settings. A digital display shows the remaining hours of light available on a single charge.

 

[easilyled]

[ QUOTE ]
NewBie said:
http://ledsmagazine.com/articles/news/2/7/20?alert=1




Cree says that the white version of the new XLamp LED is the first 3-watt product to produce a maximum luminous flux of more than 90 lumens.

[/ QUOTE ]


Surely that's not true since Lumileds 3-W U-bin claims to output a maximum of 120 lumens?

 

[rantanplan]

I think Cree refers to the typical (=nominal average) output of it´s product. I´m sure that they´ll have some better bins too. But how they evaluate these numbers ... it´s their secret, I think /ubbthreads/images/graemlins/wink.gif

But it´s nice to hear that there could be a serious competitor soon.

 

[evan9162]

I'm not a fan of wattage specs for LEDs. I'd rather know the typical Vf and test current for these specification claims.

 

[HarryN]

Evan - one reason that Cree does not usually discuss Vf much is that this is the one weakness of SiC substrate technology (also used by Nichia). The same advantage that SiC has in heat removal, adds about 0.3 - 0.5 to the Vf.

The testing I have done on Cree Xlamp (1 watt) vs Lux III indicated virtually a dead heat under similar current conditions from 50ma to 1 amp. My test setup has some weaknesses, but I consider these to be really quite competitive offerings now. There are optical pattern differences which need to be accomodated of course.

On the parts I tested, LL still had a color uniformity advantage.

 

[TORCH_BOY]

May be brighter, I wonder if they are as pure as the Luxeon 111

 

[xochi]

Hey Newbie,

Endeavours CR2 Ion is going to use this cree led. Just an FYI.

 

[easilyled]

Yes - but even their claim is NOT brighter than a U-bin LL.

Its says a MAXIMUM luminous flux of 90 lumens, not a nominal average one, as was suggested by rantanplan despite the fact that the word maximum was in the quotes /ubbthreads/images/graemlins/wink.gif

Nothing has been mentioned about efficiency though - it may well be that the Cree is more efficient than LL - I think there are claims of 60 lumens at 350ma for the 1W Cree.

However if colour rendition is superior in LL, it may take more than this for a mass conversion!

 

[alfaman]

I read somewhere the claimed lumens is @ 700mA.

 

[idleprocess]

60 lumens at 1W
90 lumens at 3W

1.5x lumen increase for a 3x power increase.

Why do I continue to be underwhelmed?

EDIT:

Looks like the efficiency numbers didn't take too much of a hit with doubling of current - assuming maximum Vf and middle-of-bin flux. The "1W" part is closer to 1.5W, so it's closer to being a linear shift.

 

[jtr1962]

Why don't they just use a larger die for the 3 watt so they could get ~180 lumens? The relatively poor efficiencies for many power LEDs are because of excessive current density.

Also, considering that Cree has already lab tested LEDs with 100 lm/W I'll have to say I'm underwhelmed as well. 30 lm/W is yesterday's news. Even cheap HK 5mm LEDs are doing better than that these days.

 

[NewBie]

I don't know where you get your 4.5V numbers from idleprocess, or your 4V numbers at 350mA, but those are the Absolute Maximum Vf, which throws off your lm/W calcs, biasing them low.

See here:
http://www.cree.com/Products/Lighting/downloads/XLamp3_7090_BL.pdf
and
http://www.cree.com/Products/Lighting/downloads/XLamp7090_B&L.pdf

For the rest of your calculations in your database, you are using Vf typical.

I've tested hundreds of them at 350mA, and have never yet seen one with a Vf close to 4V. Typically, it ranges from 3.39 to 3.7V on the blue and whites. Now their UV parts do approach 4V...

 

[NewBie]

Just to be sure, since I have some I've purchased myself here at home, I just went out into the garage and hooked one up, and I am getting 3.4 Vf at 350mA off a N bin sub bin 001, color bin WC.

 

[idleprocess]

Cree has neglected to provide as much guidance in their datasheets or binning documents as of yesterday, when I downloaded updated documents.

The table from the relevant datasheets:
1W
3W

I have only datasheets to work with, NewBie, and Cree has declined to provide a Vf range. Their binning spec doesn't seem to include voltage bins, either.

I'm working on a new version of the LEDDB, and I might put in the lower Vf of 3.39, but unless they include a range, it's going to be tough to put that in without some qualification.

 

[NewBie]

I got a pile of these, haven't had a chance to use them yet, maybe if I get some time, I'll look at the Vf on these too.

 

[AilSnail]

looks like a huge source of light. are they any good for focusing?

 

[HarryN]

The dome of the Cree behaves optically more like a 5mm from my experience. Standard reflectors work, but an Xlamp specific setup works better, as you would expect.

 

[Kiessling]

The Aleph19 head is specifically designed for the Cree (UV) and will give you a concentrated flood wth the LED.
bernie

 

[NewBie]

Evan - one reason that Cree does not usually discuss Vf much is that this is the one weakness of SiC substrate technology (also used by Nichia). The same advantage that SiC has in heat removal, adds about 0.3 - 0.5 to the Vf.

The testing I have done on Cree Xlamp (1 watt) vs Lux III indicated virtually a dead heat under similar current conditions from 50ma to 1 amp. My test setup has some weaknesses, but I consider these to be really quite competitive offerings now. There are optical pattern differences which need to be accomodated of course.

On the parts I tested, LL still had a color uniformity advantage.

HarryN....

The substrate diode is not placed in series with an LED.

If you look carefully inside the LED, you will notice two wires. One goes to the metalized top surface of the diode, which goes to one side of the light emitting die, and another which goes to the other surface of the light emitting die. The other end of the substrate ESD diode is directly bonded to the pad.


Thus the SiC does not add to the Vf.


I've seen plenty of the CREE parts that are in the 3.3 V range, some that are down at 3.2V. I've also seen some up at 3.8V. I'd have to say, 3.3V is pretty darn average.

That said, I have noticed the CREE UV parts seem to have a tendency to be a little higher in Vf.

 

[Amonra]

The 3 Watt Cree XLamps, optcs and multiple optics can be purchased here : http://www.cutter.com.au/search.php?nobox=&scat=&stext=led&stype=&sprice=&pg=2