# Cree XP-E2!



## foxtrot824 (Sep 20, 2012)

Just saw it on Cree's site. I see lots of throw coming up 

http://www.cree.com/led-components-and-modules/products/xlamp/discrete-directional/xlamp-xpe2


----------



## Brisse (Sep 20, 2012)

Good news i guess...


----------



## Gunner12 (Sep 20, 2012)

Ooo, I like this news. I hope they update all the other emitters too.


----------



## jtr1962 (Sep 20, 2012)

I'm glad to hear this. I designed and half built a bike light using 6 XP-Gs only to discover that XP-Es will give me more throw even though the number of raw lumens is less. This new announcement basically means higher-binned XP-Es and even more throw!


----------



## mossyoak (Sep 20, 2012)

Oh hell yes.


----------



## BenChiew (Sep 20, 2012)

Yahoo.


----------



## A10K (Sep 20, 2012)

Oh crud, I didn't think they'd do it... now I have to go eat my words in the XM-L2 thread.


----------



## darkknightlight (Sep 20, 2012)

Sweet! I can't wait to mod a mag with one of these.

Sent from my DROID RAZR using Tapatalk 2


----------



## climberkid (Sep 20, 2012)

When will the madness stop!


-Alex


----------



## foxtrot824 (Sep 20, 2012)

I see triples throwers in my future...


----------



## phantom23 (Sep 20, 2012)

Well, I'm not sure if it will throw better than XP-G2. XP-E2 has just slightly tighter beam angle (the difference is smaller than between old XP-E/XP-G) but it's less efficient - gives less light. I think they can be pretty close.


----------



## darkknightlight (Sep 20, 2012)

I agree they will probably be close, but doesn't the smaller die size of the xp-e2 play to its advantage as well?

Sent from my DROID RAZR using Tapatalk 2


----------



## Gunner12 (Sep 21, 2012)

This could mean more throw from a smaller reflector compared to the XP-G (assuming similar drive current).


----------



## bshanahan14rulz (Sep 21, 2012)

divergence will be lower compared to xp-g and g2.


----------



## ahorton (Sep 21, 2012)

Very excited!


----------



## mossyoak (Sep 21, 2012)

darkknightlight said:


> I agree they will probably be close, but doesn't the smaller die size of the xp-e2 play to its advantage as well?
> 
> Sent from my DROID RAZR using Tapatalk 2



I think it really boils down to more perceived throw because there is less flood.


----------



## orbital (Sep 21, 2012)

mossyoak said:


> Oh hell yes.





^^^^ :laughing:,,:twothumbs


----------



## bose301s (Sep 21, 2012)

Glad to see another one released. I do hope we release an XM-L2, would be awesome. I wouldn't hold out hope for an XR-E2 though, 5+ year old LED probably won't be updated.


----------



## Gunner12 (Sep 21, 2012)

bose301s said:


> Glad to see another one released. I do hope we release an XM-L2, would be awesome. I wouldn't hold out hope for an XR-E2 though, 5+ year old LED probably won't be updated.


One can wish...

Maybe I'll try to find really short focal length lenses for aspherical mods with the XP-E2.


----------



## darkknightlight (Sep 21, 2012)

mossyoak said:


> I think it really boils down to more perceived throw because there is less flood.



Thanks for the heads up; i need to build a light with minimal spill, but I'm not particularly a fan of aspherics or TIR lenses, so it sounds like this might be the emitter for me!

Sent from my DROID RAZR using Tapatalk 2


----------



## tstartrekdude (Sep 23, 2012)

Two days after a new led from cree comes out and not a word has been spoken about it from saabluster...eerie.


----------



## Toaster79 (Sep 24, 2012)

tstartrekdude said:


> Two days after a new led from cree comes out and not a word has been spoken about it from saabluster...eerie.



Obviously he's doing some testing


----------



## vestureofblood (Sep 24, 2012)

Are these available for purchase yet? If so where?


----------



## fyrstormer (Sep 24, 2012)

Because the E-size die is smaller than the G-size die, it would take more electricity to produce the same luminous flux (due to decreasing efficiency as the power density increases). However, if you can drive the E-size die harder to produce the same luminous flux, the E-size die will be easier to focus, because all of the light will be coming from an area closer to the focal point of the reflector/lense/TIR optic.


----------



## ergotelis (Sep 25, 2012)

this emitter will throw a lot more than xp-g2 at the same current.


----------



## phantom23 (Sep 25, 2012)

I'm not so sure, I think there won't be a huge difference like between classic XP-E and XP-G.


----------



## Glenn7 (Sep 25, 2012)

I have 2 LUX-RC FL33's and the XP-E triple throws twice as far as the triple XP-G - of course XP-G has more overall lumens OTF but because XP-E is much narrower it looks just as bright outside in real world use. the thing with XPE is you can put a defuser on it to get similar beam pattern as XPG (XPG your stuck with flood only)


----------



## fyrstormer (Sep 25, 2012)

phantom23 said:


> I'm not so sure, I think there won't be a huge difference like between classic XP-E and XP-G.


Physics says otherwise.

Unless of course the XP-E2 emitter is somehow a different design than the XP-G2, in a way that causes it to be floodier to start with.

Personally I like the XP-G emitters. They have the right balance of brightness, flood, and throw for my usage. If I want something throwier, the X*R*-E is pretty much impossible to beat.


----------



## HumanLumen (Sep 25, 2012)

Any clue on the die size? 0.9mm or 1.0mm

HL


----------



## jellydonut (Sep 25, 2012)

Yeah, Mr. White! Yeah, science!

Yeah, surface brightness, in all seriousness. Lumens per watt are well and good, but most of all we really need progress in lumens per square millimeter on the LED front. They've already trounced HIDs in the efficiency department.


----------



## phantom23 (Sep 26, 2012)

fyrstormer said:


> Physics says otherwise.
> 
> Unless of course the XP-E2 emitter is somehow a different design than the XP-G2, in a way that causes it to be floodier to start with.


It doesn't! Emitter characteristics say that the difference won't be as big as between first gen LEDs. Thing is - the difference between beam angle is smaller, while the difference between luminous flux is bigger now and those two values are quite important for throw.


----------



## 2000xlt (Sep 27, 2012)

20% more lumens per watt!! with that in mind what would the OTF lumens of the SF Fury be if the same driver was used but this LED


----------



## phantom23 (Sep 27, 2012)

Less than stock. XP-E2 has 20% more lm/W than old XP-E but it's still less efficient than XM-L.


----------



## moozooh (Sep 28, 2012)

Fury is rated at 500 lumens (OTF?). Which means it's driving the XM-L at 1600..1700 mA to achieve that brightness. XP-E2 officially goes up to 1000 mA, and at that point you'll be lucky to have 250 lm OTF; any more without proper cooling, and you have a very good chance of frying the LED. It's also likely that without a reflector optimized for its much smaller size you won't be getting higher throw either.


----------



## IMSabbel (Sep 28, 2012)

phantom23 said:


> Less than stock. XP-E2 has 20% more lm/W than old XP-E but it's still less efficient than XM-L.



Totally depends on the current...


----------



## phantom23 (Sep 28, 2012)

2000xlt said:


> 20% more lumens per watt!! with that in mind what would the OTF lumens of the SF Fury be* if the same driver was used but this LED*





IMSabbel said:


> Totally depends on the current...


Am I missing something?:thinking:


----------



## IMSabbel (Sep 28, 2012)

phantom23 said:


> Am I missing something?:thinking:



The efficiency curve peaks at different currents for different die sizes.

The bigger the die, the higher the darkcurrent, thus lower efficiencies at low currents. For example, I have a SST-90 who will produce zero light at 1mA, while an cree X-re starts to produce light at 150nA.


----------



## phantom23 (Sep 28, 2012)

XM-L is more efficient than XP-E2 in basically every current. Plus '2000xlt' wrote that it's about SF Fury and he wants to change just an emitter which means current will remain the same. It doesn't matter if it's 1A, 1,5A or 2A - XM-L will be brighter. Less throwy but brighter.


----------



## Mike S (Oct 2, 2012)

I noticed today that Mouser has XP-E2's in stock and there's quite a few color temps available. 

Digikey has them as well, but is only selling in bulk.


----------



## darkknightlight (Oct 2, 2012)

Mike S said:


> I noticed today that Mouser has XP-E2's in stock and there's quite a few color temps available.
> 
> Digikey has them as well, but is only selling in bulk.



Maybe I'm looking at mouser incorrectly, but i keep seeing that they are non-stocked with a five week lead time. Would you mind describing where on the site they are in stock? Thanks!

Sent from my DROID RAZR using Tapatalk 2


----------



## Mike S (Oct 2, 2012)

Yeah, it's hard to find on there using the filters. Instead, type "Mouser XP-E2" into google. One of the first hits should be "Cree XLAMP® XP-E LEDs / Mouser". Click the link, then scroll down to the list of part numbers. It shows only the XP-E's that they have in stock.


----------



## darkknightlight (Oct 2, 2012)

Found it! Thanks for the directions. It seems that the part number that mouser lists does not match the part number that cree lists; is that normal? I have never purchased anything from mouser before. Thanks for all of your help!

Sent from my DROID RAZR using Tapatalk 2


----------



## vestureofblood (Oct 2, 2012)

Just to be certain, this would be an XP-E2 R3 @ 122 lumens correct?
http://www.mouser.com/ProductDetail...=sGAEpiMZZMu4Prknbu83yzzUDwRnM18a7S3eg3pGUCM=


----------



## Mike S (Oct 3, 2012)

darkknightlight said:


> Found it! Thanks for the directions. It seems that the part number that mouser lists does not match the part number that cree lists; is that normal? I have never purchased anything from mouser before. Thanks for all of your help!



The big component suppliers don't usually get specific bins. Instead they'll show a kit code, which you can decipher by going to Cree's XP Family Binning & Labeling document. The PDF's can also be found on Cree's website. 

A specific kit code will often have one particular flux bin, but the chromaticity bins will vary. Some codes are grouped tighter than others. It's good to look at that document before ordering from a site like Mouser.



vestureofblood said:


> Just to be certain, this would be an XP-E2 R3 @ 122 lumens correct?
> http://www.mouser.com/ProductDetail...=sGAEpiMZZMu4Prknbu83yzzUDwRnM18a7S3eg3pGUCM=



Yep, page 25 is showing R3 bin for the code you linked. Kit 50 is made up of chromaticity bins 1A, 1B, 1C, 1D, 2A, 2B, 2C, 2D.


----------



## vestureofblood (Oct 3, 2012)

Do XPEs have the same foot print that XPGs have? PCBs are interchangeable correct?


----------



## fyrstormer (Oct 3, 2012)

phantom23 said:


> It doesn't! Emitter characteristics say that the difference won't be as big as between first gen LEDs. Thing is - the difference between beam angle is smaller, while the difference between luminous flux is bigger now and those two values are quite important for throw.


As long as the XP-G2 die is wider than the XP-E2 die, the beam *will* be floodier. Optics can only focus perfectly the light coming from the exact focal point, which is the middle of the emitter die assuming the emitter is positioned correctly. A wider emitter will emit more of its light from points further away from the optic's focal point, so the beam will be wider and blurrier. There is no possible way to avoid this phenomenon. Even if the emitter were designed so most of the light came from the center, the small amount of light coming from the edges would still be out-of-focus and the beam would still be wider than it would be with a smaller emitter.


----------



## phantom23 (Oct 3, 2012)

I just wrote that the difference will be smaller between XP-E2/XP-G2 than between XP-E/XP-G. XP-E2 will be slightly throwier than XP-G2, but not as much as XP-E vs. XP-G.


vestureofblood said:


> Do XPEs have the same foot print that XPGs have? PCBs are interchangeable correct?


Yes, that's correct.


----------



## darkknightlight (Oct 3, 2012)

Thanks every body for all of your informative help!

Sent from my DROID RAZR using Tapatalk 2


----------



## fyrstormer (Oct 4, 2012)

phantom23 said:


> I just wrote that the difference will be smaller between XP-E2/XP-G2 than between XP-E/XP-G. XP-E2 will be slightly throwier than XP-G2, but not as much as XP-E vs. XP-G.


I was never arguing about the *magnitude* of the difference between the two emitters, only the *existence* of a difference between the two emitters. It's a judgement call whether the additional throw from the smaller XP-E2 emitter is worth the trouble of driving it harder to produce the same flux, and there's no way to quantify personal preference. There will be plenty of people who will opt to use the throwier emitter regardless of *how much* throwier it is.


----------



## BLUE LED (Oct 12, 2012)

I have been having so much fun with the XP-G2 and now the excitement continues. The XP-E2 should work well with lights that use small reflectors. I already like the XP-E R4 in my small light and looking forward to trying the XP-E2


----------



## vestureofblood (Oct 12, 2012)

I ordered some of the emitters via mouse house. The color of the ones that came to me are a very clean cool white. I picked up some 11 ish MM PCBs from illumination supply so they would fit the opening of a mag rebel reflector without boring. Makes for a clean tight hot spot for sure.


----------



## ahorton (Nov 1, 2012)

I just had 6 XP-E2 R3s arrive from Cutter today.

First thing I did was test them at 1.4A behind aspheric lenses. The projected images look a little different to what we're used to from the old current spreaders. Now they have little dimples in the beam instead of lines.

In terms of intensity (throw) they performed almost exactly the same as the old XR-E (EZ1000). I was a little upset at this.

Then I got excited when I realised that they had a Vf of about 3.18-3.2V. The XR-Es were up in the 3.7-3.9V range. So this means a big improvement in runtime and regulation for those of us who like linear and direct drive setups.

All tests were done on similar quality MCPCBs. The XP-E2 will probably gain a little more than the XR-E when soldered directly to copper since it has a smaller pad and slightly higher thermal resistance.

Bottom line for aspheric use:
No better performance than the XR-E, but much longer runtimes and/or regulation.


----------



## orbital (Nov 1, 2012)

ahorton said:


> .....Bottom line for aspheric use:
> No better performance than the XR-E, but much longer runtimes and/or regulation.



+

That's efficiency:

*More runtime with same performance* {same energy used}

_or_

*Same runtime with more performance* {same energy used}


----------



## ahorton (Nov 1, 2012)

orbital said:


> +
> _...
> or_
> 
> *Same runtime with more performance* {same energy used}



That's another test which I haven't done yet, but I'm guessing that the XP-E2 can't be driven harder than the XR-E in a similar setup. Also, the XR-E was much easier to solder directly to copper/brass or glue directly to anodised aluminium (soldering connections on top).

So I think we're limited to the same performance with longer runtimes.


----------



## phantom23 (Nov 1, 2012)

ahorton said:


> Bottom line for aspheric use:
> No better performance than the XR-E, but much longer runtimes and/or regulation.


No better performance with aspheric lenses! That makes a huuge difference! XR-E is great in that setup because of tight beam angle. "Old" XP-E had similar performance - brightness, efficiency etc. bit it gave less throw with aspheric lenses because of wider beam angle. If XP-E2 matches XR-E with aspherics, it's because of its brightness/efficiency and it should rock with classic reflector.


----------



## bshanahan14rulz (Nov 1, 2012)

^XR and XP packages are vastly different, I wonder what the common belief is, as to which one has the least thermal resistance from LED die to thermal pad... XR looks like it has the die on a larger piece, what looks like an SiC heat spreader, so heat would go from die to heat spreader to ceramic to thermal pad. XP looks more like die mounted on the substrate, but with nothing to spread heat to a larger cross section before going through ceramic.


----------



## ahorton (Nov 1, 2012)

bshanahan14rulz said:


> ^XR and XP packages are vastly different, I wonder what the common belief is, as to which one has the least thermal resistance from LED die to thermal pad...



The datasheets say:

XR-E thermal resistance: 8 K/W
XP-E2 thermal resistance: 9 K/W

However, with an MCPCB, the main factor in the overall thermal resistance (junction to atmosphere) is the dielectric layer. Unless an extremely thick copper layer is used on the MCPCB, we're really only interested in the area directly under the pad. 

Pad sizes:
XR-E: 36.176 mm^2
XP-E2: 3.84 mm^2

So for the same dielectric layer (say 0.10mm thick, 2.00W/(mK), and assuming that the LED's solder pad is a perfect heat spreader, the thermal resistances will look like:

XR-E: 1.38 K/W
XP-E2: 13.0 K/W

In more meaningful terms, in a similar setup (say 1.4A), with say 50% of energy going into heat, you can expect the dielectric layer under the XP-E2 to cause an extra (0.5)x(3.2x1.4)x(13.0-1.38) = 26 K hotter and shine about 7% dimmer once it's warmed up (compared to an XR-E).



Bottom line: The performance gain for soldering direct to copper is much greater for the XP-E2. Sadly it's much harder to do.


----------



## OneBigDay (Dec 9, 2012)

In general terms can somebody comment if the XP-E2 will still out-throw the XP-G2 even without either emitter being overdriven?

AFAIK this would be...

XP-G2 driven at 1.4 amps
XP-E2 driven at 1.0 amp

Or does the XP-E2 need to be over-driven (to say 1.4 amps) in order to out throw the XP-G2?

When buying "stock" lights I think this will be an important point to know because most manufacturers are not going to overdrive the emitters. This would take most of the "throw advantage" being discussed around this emitter out of the stock realm and put it only into the modding realm or only for over driven modules offered by forum members.


----------



## ahorton (Dec 9, 2012)

Even at a lower current (1.0A vs 1.4A), I would expect the XP-E2 to out-throw the XP-G2. 

The surface brightness is what matters in with reflectors, TIR optics, and behind PCX lenses. Even if the XP-G2 had 40% more flux, it would still be spread over 100% more surface area compared to the XP-E2.

This assumes identical die properties. If you use similar bins for flux and tint, then the above should hold.


----------



## BenChiew (Dec 31, 2012)

I have got 2 of Mac's Tri EDC coming in. One has a triple xpg2 and the other a triple xpe2.
It would be interesting to see if a layman can visually pick up any difference in the throw on these 2.

I was told that XPE2 has about 15% less overall lumens but has 1.5x the throw.


----------



## Glock 22 (Dec 31, 2012)

This led is what Surefire should have put in there new EB1, then it may have been better light, with better runtime and would stay in regulation better.


----------

