# Is this a CREE LED??



## eebowler (Jan 3, 2008)

Pic of Q5 from Endevour's group buy

Pic of Cree removed from L2D

Pic of DX, Cree Elly

Die pattern of DX, Cree Elly.

I got it from kaidomain and it's listed under "Cree LED flashlights" The output is comparable to my DX, Cree Elly powered by a MiniPro III (900mA current draw). I'm trying to get the link now.
Got it SAIK RC-A2


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## AzGB (Jan 3, 2008)

While the actual die pattern doesn't look like what I'm used to as being a Cree, you did notice what it says right? I'm not being a smartass, by the way, sometimes I miss things that are right in front of me...

:thinking:


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## eebowler (Jan 3, 2008)

LOL AzGB. I did saw that but, it's from china and they lable anything as they please. When Luxeon LEDs was the only thing you could get, there were lots of odd LEDs looking like Luxeon stars popping up with 'Luxeon LED' stamped on the stars yet, they were fake.


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## AzGB (Jan 3, 2008)

eebowler said:


> LOL AzGB. I did saw that but, it's from china and they lable anything as they please. When Luxeon LEDs was the only thing you could get, there were lots of odd LEDs looking like Luxeon stars popping up with 'Luxeon LED' stamped on the stars yet, they were fake.


 
Ok... gotcha. Sorry for the lack of faith there. I was hoping there was more to it than just a simple oversight.


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## kenzo (Jan 3, 2008)

Isn't that a Cree p2?


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## J.D. (Jan 3, 2008)

I think it is a cree Emitter, i would say xr-e Bin: *P2
*as far as i know the
p2 bin has only 2 wires to the diode
p4 bin has 3 wires
and the Q bins has 4 wires

just my opinion ...


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## J.D. (Jan 3, 2008)

kenzo was faster


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## chimo (Jan 3, 2008)

Possibly a Cree XR-*C*. Looks like Cree's EX600 or EZ700 die (not the EZ1000).

Paul


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## Jay T (Jan 3, 2008)

J.D. said:


> I think it is a cree Emitter, i would say xr-e Bin: *P2
> *as far as i know the
> p2 bin has only 2 wires to the diode
> p4 bin has 3 wires
> ...



Doesn't that go against the concept of "binning"

Binning is where they are manufactured, then tested and sorted according to performance. They don't know what they are until after they are manufactured.

Taking a look at my Bug out gear Premium+ it has four wires, and it's a P4 bin.

My Hyperion CER was listed as a P4 and it has 4 wires.


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## J.D. (Jan 3, 2008)

So it looks like i´m wrong ...
i have several P4 bins - all with 3 wires
and one p2 bin - with one wire
and 10 Q5 with 4 wires.

maybe that was coincidence ...

but i think my thoughts didn´t go against the concept of binning.
sure you are right the leds are sorted after production.
but i think in the first time when the first XR-E p4 was availible there where no Q5 availible.
So i think the technologies has moved on form p4 to q5 and my thoughts was that cree put anoter wire to the die.

but as said - maybe i was wrong :nana:


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## SteveDavis (Jan 3, 2008)

That is an XR-C. The way to tell is to look at the die itself, not the substrate. In an XR-C, the die is smaller, has only two rectangles created by the on die wiring, and only one wire bond to the die. The XR-E has two wire bond locations on the die, and three rectangles created by the on die wiring. Both have the same package, so package size and footprint will tell you nothing.


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## eebowler (Jan 3, 2008)

chimo, SteveDavis: It looks like you guys are correct. I've been looking at the document chimo provided and they do look exactly like what I have. These dies are used to make the XR-C LEDs as you suggested.

The EZ1000 die seems to be that of the P4-Q5 LEDs.

Now I have to figure out if I the LED sucks or not.

Edit: It seems they are equal to or lower than a P2 cree wrt lumens per watt output. This isn't good. I think I'll change the LED IF I can get it off the board...


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## SteveDavis (Jan 3, 2008)

For re-working a board like this, I recommend using a hot plate set to 230 deg C. Some people also claim success using an electric range, but I would use a lot of caution when using something that imprecise. Leaving the board on too long could kill your LED.


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## eebowler (Jan 3, 2008)

LOL. I don't have a hotplate. Haven't seen one of those in years.  I'll have to heat it over the stove top and see what happens. It's not like loosing the XR-C will kill me though.


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## Gryloc (Jan 4, 2008)

Hmm. I did not know what made the XR-C different from the XR-E. I thought that they could be binned as much lower flux emitters. That does explain where the EZ700 die is used. It also explained why these are considered by Cree to be the super-value emitters. Thank you for the detailed pictures!

If the flux is decent (maybe equivalent to a XR-E P4), even if the efficiency is not the best, then this emitter would still have some decent uses. For example, due to the smaller die size, this would work great behind an aspheric lens! This would have a more laser-like beam in comparison to the XR-E. I am not sure how noticeable the difference would be, but it would be an interesting experiment. Otherwise, this would work great in a bunch of cheap and easy upgrades from the older Luxeon I and III emitters.

Thanks again for the info. Now I know to be more cautious when ordering a flashlight from DX or KD that features a "Cree". Atleast it is an authentic one and not a fake, like the many "Fakeon" flashlights of yesterday.

-Tony


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## VanIsleDSM (Jan 4, 2008)

are you sure any of these 2-3 wire ones aren't just china copies? every single CREE I've had, P3, P4, and Q5 have all had 4 wires.


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## eebowler (Jan 4, 2008)

Gryloc, from my understanding of the documents, these XR-C LEDs arn't even as efficient as the P4s. Yeah the die is smaller but what's the point if it's less efficient.

I have two Cree DX Elly flashlights. One with a MiniProIII converter and one with a Micropuck. With respect to overall brightness (roof bounce,) the Saik is in between both of these lights (closer in brightness to the MiniPro.)

Current draw:
Micropuck Hi : 0.43A
MiniProIII : 0.94A
Saik RC-A2 : 1.88A!

I think this says alot.

SteveDavis: I tried to bond a Cree to a copper coin over the stove (another project) but apparnetly heated it too much, seperated the die from the slug and blew the LED when I ran it on high current. I'll have to buy a cree star from someone and cut it down or fit in a Seoul star from PhotonFanatic.


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## SteveDavis (Jan 7, 2008)

This is why I recommend buying a hot plate. Failing that, I think it's best if you have some way of getting an accurate temp reading off of your stove. Maybe the best thing would be to use a cast iron pan and a good thermometer, I'm not sure. Also, look at the manufacturing instructions on the XR-E datasheet. I believe that the LED is only supposed to be exposed to the full soldering temperature for under 30 seconds.

These LEDs were not designed for the hobbyist, they were designed for professional manufacturing processes, so when attempting to do anything like this at home, you have to be extremely careful, and expect that no matter what you do, something catastrophic could happen.


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## Lightingguy321 (Jan 7, 2008)

The LED in the picture is definetly a Cree-XRC.


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## eebowler (Jan 7, 2008)

Yeah, something catastrophic did happen 

I changed the LED to a P4 (I assume) from DX. The increase in brightness is only slight and the current draw increased to 2.03A. It's just slightly dimmer than the MiniPro powered light now.

The converter seems to be the low efficiency culprit here. I'll change it out as soon as possible and put in maybe a MiniProIII or a micropuck.


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## WeLight (Jan 8, 2008)

This part is an Cold White XR-C. Please note these are rated at max 500mA, however the smaller die does have some advantage when used with TIR Optic Example

Led XR-C XR-E 
Lumen at 350mA 60 80 
Peak Intensity*/Lumen 
using Cree XLSL 247 47 cd/Lm 24cd/lm 
Peak Intensity 2820cd 1920cd 

Please note this is with optics not reflectors

*Intensity numbers are not given as a specification and are only used for comparison purposes


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