Cree quietly updated xm-l2 led emitter

Flashlight Modding and DIY Parts
1

Hello guys, it seems like i am back for good.

I did some research after some new xm-l2 emitter appeared in KD.
Have some of them on the road, should arrive sometime this or next week, already shipped.

Here is an interesting fact i found. Cree, updated xm-l2 emitter, without mentioning somewhere anything!
From what i see, it is now a direct and maybe better comparison to sst40. I took data from the official datasheets.

Here are some specs that we know of the common leds now:

xm-l2 old: Thermal resistance 2.5C/W , min lm 340lm@0.7amp, Vf ~3.6V @ 3amp

sst40 : Thermal resistance 1.2C/W , min lm 320lm@0.7amp, Vf ~3.1V @ 3amp

xm-l3 : Thermal resistance 2.2C/W , min lm 340lm@0.7amp, Vf ~3.15V @ 3amp

And now:
xm-l2 new: Thermal resistance 0.75C/W !! , min lm 340lm@0.7amp, Vf ~3.02V @ 3amp !!

What are your thoughts?

2

Everything is believable, except for the 340lm/W claim, unless it was a green emitter.

340lm/W out of an LED, a single high power one no less(unless it was a multi-die LED, but that would still be extremely far-fetched), would be an industry breaker.

I’m also going to need a link.

Also, your other figures seem to be off as well. Ain’t no SST-40 going to reach 300lm/W today lmao.

3

sorry my mistake, had to mention @0.7amp . fixed it now. My bad sorry the daemon of writing striked me hahha
The datas are from the official datasheets you can check them.

4

Holy moly!

That is obscenely good.

0.75C/W and a Vf of 3.02V at 3A….

5

Thanks for the info. I think a few of us were confused by that KD listing.

6

Here's a flashlight with one XM-L2 LED that outputs 5000 lumens...

https://budgetlightforum.com/t/-/29803/5610

It's on sale, too!

7

At Aliexpress you can find way more lm from one xm-l2! 5000 only?! Too low!

8

@raccoon city, with the new super low VF and thermal resistance, maybe we’ll finally be able to see 5000 lumen XM-L2 lights lmao.

9

How you compared this new XM-L2 to XM-L3?

10

Check original post, i have included such comparison

11

Oh, I somehow missed that. Thanks

12

I am slightly confused about this post, or mostly some of the comments lol, and Vf, and outputs. I dont understand, but i did order some XML from Kaidoman yesterday, the 7A3 variant, and 4C variant too. Im just hoping for good tint lol. Not hopeful for 4C bin, but 7A3 could be quite good, i have pretty good 7A3 bin xpl-hi.

13

How can you tell which XML is the old version and which is the new?

14

You can look at pictures here:
http://kaidomain.com/Flashlight-DIY-and-Tools/LED-Emitters-or-LED-Star-on-PCB/CREE-XM-L-Series-LEDs

It appears the new XML2 is a flip chip (no bond wires) with a white silicone surrounding the die, similar I think to the XHP50.3.

15

Why would a company hide such an upgrade when they are working full time on marketing a ‘’new’’ product that is almost the same as the last one but claim its revolutionary to boost sales?
Or it is just that the manufacturing process is now the same for the old and new models.

16

Maybe the “color over angle” will be improved from this change.

17

ergotelis I’m sorry, but I think that you have experienced “!#$%^ specification syndrome" - somebody have !#$%^ up copy & paste process and you have assumed that it’s true…

18

@DominikM, it is obviously not.

Everything is in the datasheet:

19

Besides a ~20% boost in output, I’m guessing the lower resistance will mean less heat generated, am I correct?

20

Well, that’s a bit complicated, and depends on the driver. A switching (buck or boost) driver would see less heat generation because it would be delivering lower voltage to the LED at the same Amps, so lower power consumption.

A linear driver would be doing the same, except it has to burn off that extra voltage at the driver, so it basically ends up being a wash, though it will stay in regulation a bit longer.

A FET will end up delivering more current due to the lower total resistance, so you may actually see more heat.