TorchBoy
Flashlight Enthusiast
That sounds like a great idea too.
Quad cree led !
- Thread starter vincebdx
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Its funny, as I was about to push the "submit reply" button on that post it occurred to me that it was probably incorrect. Then my next thought was "It's ok. Evan will be along shortly to clean up."Thanks. This is one area I've been needing to really buckle down and try to wrap my brain around the formulas involved.
I HATE math. So I've been avoiding it.
Maybe you can help clear up something else as well. I was trying to look up the specs for the P7's thermal performance as compared to the new Cree MC-E and found two different results. This one says 7.5 C/W and this(must click on the "W724C0" spec pdf at bottom) one 3 C/W. Why such a different spec for what appears to be the same part?
The info for the first link has got to be a mistake. The P4 is already 6.9C/W - I can't see why the P7 would be higher.
I wonder if they mixed up some of the specs with another product (i.e. copied the table form over from an existing web page, and didn't change all the fields). At any rate, I'm saying that the datasheet is correct. It's the one that makes sense.
Some thoughts:
- Nice general illumination product
- Emission pattern is not even remotely like XR-E and hence don't expect it to behave anything like the XR-E. You would be better off digging out your Lux-V optics.
- Lambertian pattern....will actually make the XR-E behave better in reflectors
- Source size is going to be huge... over 2x the size of the XR-E and likely 3X the size for the Rebel. Keep that in mind. To get similar "throw", you need a reflector proportionally larger to get the same level of "focus". It will be a simpler, but not smaller unit to get the same throw.
- May not be easy to focus on one LED dependant on the effect of the dome. The dome does have an optical effect.
- Nice they are brought out individually though I would likely drive them serially. Just a simple boost circuit and I am all done. I could even put something into the circuit on each LED such that one failure does not take the light out.
- RGBA.... problem on a single package is the heat from G and B kill the output of R and A given current die technology.
- I don't see the small leads being a problem. They look similar to an SO-8 package.
- 700mA could be 10 watts or 30C above the heat sink. Very tolerable for a flashlight. If they use the same lumen maintenance temp as XR-E (85C), then for general lighting that will require a good sized heat sink.
- When can I get it and how much?
- Nice general illumination product
- Emission pattern is not even remotely like XR-E and hence don't expect it to behave anything like the XR-E. You would be better off digging out your Lux-V optics.
- Lambertian pattern....will actually make the XR-E behave better in reflectors
- Source size is going to be huge... over 2x the size of the XR-E and likely 3X the size for the Rebel. Keep that in mind. To get similar "throw", you need a reflector proportionally larger to get the same level of "focus". It will be a simpler, but not smaller unit to get the same throw.
- May not be easy to focus on one LED dependant on the effect of the dome. The dome does have an optical effect.
- Nice they are brought out individually though I would likely drive them serially. Just a simple boost circuit and I am all done. I could even put something into the circuit on each LED such that one failure does not take the light out.
- RGBA.... problem on a single package is the heat from G and B kill the output of R and A given current die technology.
- I don't see the small leads being a problem. They look similar to an SO-8 package.
- 700mA could be 10 watts or 30C above the heat sink. Very tolerable for a flashlight. If they use the same lumen maintenance temp as XR-E (85C), then for general lighting that will require a good sized heat sink.
- When can I get it and how much?
Daekar
Enlightened
So, how can we best utilize this puppy? Obviously, increasing the "glass ceiling" is a plus, but what about underdriving? Assuming you have a driver for each core (which is probably the safest) it wouldn't make sense to drive all 4 cores all the time because of driver losses... so if you wanted to run on "low-low," you just power one core. Kick it up to 40 lumens, it might make sense to run 2 cores, but not all 4. This would, of course, require intimate knowledge of driver efficiency at any given current so you could determine the optimal transition points for adding another emitter/driver combination. The only snag is that multiple drivers take up more space, so if we see these appear in EDC-size lights I think they'll be 1 or 2 driver lights only, running the cores 2s2p or 4s0p for a single-driver and 2s0p for double-drivers. Of course, if you have multiple REALLY efficient one-level drivers you could just turn drivers/cores on and off for a 4-level light...
Oh the possibilities...
Oh the possibilities...
rizky_p
Flashlight Enthusiast
WOW nice one, and keeping the same footprint while packing 4 dies. I like this more than the ugle large P7. Come on Cree bring it to the market. Will need to buy new mag body then
Guys imagine this and and aspherical Lens
On page 7 in the PDF file, there is a drawing with each of the four LED connected to single zener diode in paralel, what is it for? reverse current protection?
Thanks.
Guys imagine this and and aspherical Lens
On page 7 in the PDF file, there is a drawing with each of the four LED connected to single zener diode in paralel, what is it for? reverse current protection?
Thanks.
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Marduke
Flashaholic
An just think, what we see now is the bottom end of the line. The brightness and efficiency can only go up as they perfect the process and make improvements!!
jtr1962
Flashaholic
Even the worst bin (370 lumens minimum @ 350 mA per die) comes out to over 80 lm/W. Can't wait to see where these are this time next year. I think 550+ lumens at 350 mA per die will be a very real possibility.
Mike Painter
Flashlight Enthusiast
- Joined
- Sep 16, 2002
- Messages
- 1,863
The thread " Cree Demonstrates New XLamp Multi Chip Led " has more info and the first post talks about optics...
FredM
Enlightened
So if used in series/p it would need about 1.5amps at ~7volts right?
mmmflashlights
Enlightened
- Joined
- Mar 24, 2007
- Messages
- 345
So THIS is what Mag has been delaying the release of its LED-based Solitaire for. 
TorchBoy
Flashlight Enthusiast
So THIS is what Mag has been delaying the release of its LED-based Solitaire for.
Hit the AAA with a 5.8 amp draw. Make it suffer! Mwa ha ha ha.
Just a thought, but I wonder if they are still mounting the chips on SiC with the MC-E. Seems it would be difficult to do in this configuration.
Jarl
Flashlight Enthusiast
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Bimmerboy
Flashlight Enthusiast
I think I just wet myself
:laughing:
SiSiSilicon CaCaCaCarbide.... oooofff.
Not sure yet what to think about the MC-E. It looks exciting in many ways, and I'm sure it will have it's strong points. But, unless I'm missing something, if you want to run it in series, this thing will NOT be fun to wire up.
Holy color rendition batman!
This is great, a warm white/neutral white LED, with decent lumens per watt.
I'm freakin excited about this, but I'm so confused. Is this an LED or the holy grail? The P7 didn't have me terribly excited when it came out, but the quad cree does. I guess after EDCing an A2, and falling in love with it's color temp; I'm thrilled at the thought of a light with a couple hundred lumens, a perfect tint, and a long runtime (relatively anyhow.).
This is great, a warm white/neutral white LED, with decent lumens per watt.
I'm freakin excited about this, but I'm so confused. Is this an LED or the holy grail? The P7 didn't have me terribly excited when it came out, but the quad cree does. I guess after EDCing an A2, and falling in love with it's color temp; I'm thrilled at the thought of a light with a couple hundred lumens, a perfect tint, and a long runtime (relatively anyhow.).
ifor powell
Enlightened
It's designed to go on a board, using them raw in series will be fun... no problem parallell though. I assume we will see various boards avalible defiantly stars series wired should be expected I am not sure what else people will want? these are all potential options you may want from a board: 4s, 4p, 2s2p, 2 * 2s, 4 * 1s
Ifor
I think that I am going to have to move up my estimation for an off the shelf kilo-lumen flashlight.
Not Jan 1 2010, but Jan 1 2009
That bin (5C 5D) of sub 4000K neutral white is just crying out for a flashlight to go into. 3850K?
6A 6B look good for LED headlights. 3600K, just like the HIR highbeam bulb.
Not Jan 1 2010, but Jan 1 2009
That bin (5C 5D) of sub 4000K neutral white is just crying out for a flashlight to go into. 3850K?
6A 6B look good for LED headlights. 3600K, just like the HIR highbeam bulb.
Mike Painter
Flashlight Enthusiast
- Joined
- Sep 16, 2002
- Messages
- 1,863
AvPD
Enlightened
How long has it taken Cree in the past to get from this sort of demonstration to it's LEDS being available? The gap between SSC announcing the P7, and individuals and resellers having the LEDs was fairly short.
Cree has always been conservative in releasing a lot of their products primarily to ensure when they release, they are running down the line with 100% confidence in the product doing all they have promised. This is a new package, albeit the same physical size as XLAMP and they will fully test through the manufacturing process to ensure you get what you have come to expect from Cree. They have stated the product will be available in this quarter and we expect to load orders in July.
I believe it will be worth the wait
