znomit
Enlightened
5mm x 5mm, or 5 square mm?
Cree does it again-160 lumens per watt @350 mA
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5mm x 5mm, or 5 square mm?
I was wondering what he meant as well but since 25 square mm would be insane I assumed he meant 5 square mm. If it is 25 square then I am extremely underwhelmed to say the least.
They say it will be two months until samples are even ready. Although I'm sure Cree will get this to market within the year as they expect it seems a bit premature to put out this press release when you can't even get samples.:shakehead
I came to the light...
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They say it is bigger than the XP-E... they don't mention the XP-G, which would make me think it is smaller than the XP-G. However, they also say the XP-E is CREE's flagship model, so maybe the references are just outdated.
WeLight, I'm a little confused by your phrasing. Are you guessing or do you have more information?
I don't know how to request a sample, so it is possible the article's just wrong, but it would seem they are available as samples.
WeLight, I'm a little confused by your phrasing. Are you guessing or do you have more information?
CREE said:
I don't know how to request a sample, so it is possible the article's just wrong, but it would seem they are available as samples.
My Cree Rep says it's a two month wait for the new LEDs minimum. That was not a guess. Samples are not for the general public.
Well to be strictly accurate they say it has a larger footprint than the XP series, which means package size rather than die size, so the die could be anything - though it seems unlikely the die wouldn't be bigger, otherwise why not keep the same package?
Have to admit to being slightly disappointed too if the surface brightness is really less again than an XP-G (leaving the XP-E as the surface brightness champ). I've yet to go to feel the desire to build an XP-G lamp due to the difficulty of making something with decent throw compared to my old XR-E ones.
I came to the light...
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Thanks, I wasn't sure what exactly was meant by that part of the announcement. (My question about guessing was directed at WeLight)
rizky_p
Flashlight Enthusiast
can wait to see what it look like......i haven't jump on SST family yet or maybe wont. hope this would satisfy my future need
R33E8
Newly Enlightened
That's cool, I wonder if they will make a MC-XM 
I'm happy I have stock in Cree
I'm happy I have stock in Cree
kramer5150
Flashaholic
I agree with this completely. But thanks for posting this.
old4570
Flashlight Enthusiast
Looks interesting - Still waiting on the S2
Linger
Flashlight Enthusiast
So what 'we' get from this is that Cree's tech improvement permits larger chips: the multiple emitter mc-e type packages and concomitant dark cross/donut will not be salient issues in the near future.
?
?
tstartrekdude
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I am almost sure that they are just putting a xp-g die in a bigger package, it says something to the effect of "very high efficacy at very high drive currents"
2 amps is only adding 500ma's to the xp-g drive level, and with a better package it should be fine at that level. just makes the most sense the way they worded that, that its is the same die as the xp-g. so it might not be as bad for the throw mongers here as you guys think. the xr-e will still hold out as the top throwing led right now, but it should at lest keep up with the xp-e with a hot spot twice the size.
I was a good bit disappointed at the xp-g, the added lumens did not make up for the lost lux like i had wished for. so for me this will just do the jobs that i had planed for the xp-g...YAY!
2 amps is only adding 500ma's to the xp-g drive level, and with a better package it should be fine at that level. just makes the most sense the way they worded that, that its is the same die as the xp-g. so it might not be as bad for the throw mongers here as you guys think. the xr-e will still hold out as the top throwing led right now, but it should at lest keep up with the xp-e with a hot spot twice the size.
I was a good bit disappointed at the xp-g, the added lumens did not make up for the lost lux like i had wished for. so for me this will just do the jobs that i had planed for the xp-g...YAY!
znomit
Enlightened
Looking at JTRs XPG R5 numbers and adding 7% for the jump to S2 bin.
S2 XPG die hits 160lm/W at 175mA.
And 375lm at 1A x2 =750lm.
:twothumbs
But revolutionary?
S2 XPG die hits 160lm/W at 175mA.
And 375lm at 1A x2 =750lm.
:twothumbs
But revolutionary?
I suppose znomit had the same impression as I did:
From XR-E to XP-G the major improvement in efficiency was to double the die size plus throwing in some minor lab improvements. But from the given numbers in the announcement guessing is fairly easy. 160 lumen at 1 Watt eqauls a reduction of Vf down to 2.86 V at 350 mA.
Looking again in the data of JTR says : XP-G hits that Vf-level at 150 mA
Calculation of Vf at 2A: 750 lumen output at 110 lm/W means 6.82 Watts and 3.41 Volts: A bit higher than XP-G at 1A. This means the thermal path has been improved so droop is reduced.
XP-G hits 375 lumens at 1.1A so there must be improvements additional to bigger dies.
All these comparisons suggest:
They double the die size again...well I don't mind, if it's for a reasonable prize !
From XR-E to XP-G the major improvement in efficiency was to double the die size plus throwing in some minor lab improvements. But from the given numbers in the announcement guessing is fairly easy. 160 lumen at 1 Watt eqauls a reduction of Vf down to 2.86 V at 350 mA.
Looking again in the data of JTR says : XP-G hits that Vf-level at 150 mA
Calculation of Vf at 2A: 750 lumen output at 110 lm/W means 6.82 Watts and 3.41 Volts: A bit higher than XP-G at 1A. This means the thermal path has been improved so droop is reduced.
XP-G hits 375 lumens at 1.1A so there must be improvements additional to bigger dies.
All these comparisons suggest:
They double the die size again...well I don't mind, if it's for a reasonable prize !
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milkyspit
Flashlight Enthusiast
Linger, I don't really think the multi-chip arrangement itself is a sign of cheap or inferior technology as you imply... and in fact, I suspect the multi-chip arrangement will continue to be with us for some time into the future, and continue to incorporate the latest in single-core technologies, albeit with some lag time to move those technologies into the multi-core device.
Besides, multi-core (at least as designed into the MC-E) brings to the table some flexibility the single-core solutions cannot provide, such as the option of running at various voltages and with the RGB variants, blending for virtually any color across the entire spectrum. Plus it allows for all those cores to sit under one reflector, and Nailbender's Linger Special notwithstanding, that just isn't possible with single-core designs.
So to me the XM brings another tool to the toolbox... one well worth having, plus strategically valuable for Cree vs. Luminus.
As for the dark cross/donut, Cree could remove that from the MC-E in any of a number of ways... one would be a more textured dome similar to what Osram did with the Diamond Dragon. I can eliminate those artifacts, too, by any of several approaches... and there are optics/reflectors already on the market that show no donut or cross at all with the MC-E. Fraen makes one, though its part number escapes me at the moment.
Anyway, to me the XM announcement is good news! Just not due to elimination of the cross or donut hole.
BentHeadTX
Flashlight Enthusiast
I like the news,
Sure, not on the flashlight front unless you want a flood light but Cree is looking at lightbulb replacements. 750 lumens at 6.8 watts at 110 lumens per watt will be... 6.8 x .66666 = 4.5 watts of heat to get rid of. A screw in style bulb can handle 5 watts so throw in the heat from the AC to DC conversion and it now becomes possible.
Then Cree has those dice in the lab that pump 206 lumens per watt so it should migrate to that new die so maybe 850 lumens at 5.15 watts for 165 lumens per watt? That would be at the 50% heat to light ratio and "60 watt incandescent" output. You would not need exotic and expensive cooling to handle 2.6 watts of heat even throwing in another half watt for the converter.
Maybe late next year the single die LED 60 watt bulb replacements that won't overheat will be available. Figure for $25 a bulb, it will be worth replacing the CFL bulbs in the house and THAT is what I want to do.
Another option is to put 5 of those LEDs in a bulb and drive them at 5 watts total for 800 lumens. It is almost at the level of 60 watt bulbs and would not have any problem with cooling. Expensive yes, but with that configuration you could replace the bulbs in your house, get 10 times lower energy consumption, no flicker like CFL, it will run cool and no need to replace the bulbs for another 10 to 20 years.
Sure, not on the flashlight front unless you want a flood light but Cree is looking at lightbulb replacements. 750 lumens at 6.8 watts at 110 lumens per watt will be... 6.8 x .66666 = 4.5 watts of heat to get rid of. A screw in style bulb can handle 5 watts so throw in the heat from the AC to DC conversion and it now becomes possible.
Then Cree has those dice in the lab that pump 206 lumens per watt so it should migrate to that new die so maybe 850 lumens at 5.15 watts for 165 lumens per watt? That would be at the 50% heat to light ratio and "60 watt incandescent" output. You would not need exotic and expensive cooling to handle 2.6 watts of heat even throwing in another half watt for the converter.
Maybe late next year the single die LED 60 watt bulb replacements that won't overheat will be available. Figure for $25 a bulb, it will be worth replacing the CFL bulbs in the house and THAT is what I want to do.
Another option is to put 5 of those LEDs in a bulb and drive them at 5 watts total for 800 lumens. It is almost at the level of 60 watt bulbs and would not have any problem with cooling. Expensive yes, but with that configuration you could replace the bulbs in your house, get 10 times lower energy consumption, no flicker like CFL, it will run cool and no need to replace the bulbs for another 10 to 20 years.
milkyspit
Flashlight Enthusiast
I like the way you're thinking, BentHead, on all fronts. I've currently got a couple of those 45W equivalent LED bulbs from Lowe's running in the house. I must say, they're very nice. But they cost nearly $40 each and these new Cree dice would make a welcome improvement.
