XP-L2

Richard , any luck with dedoming ?

Haven't tried, but the phosphor / dome look just like what we've seen with the latest generation Crees (won't dedome very cleanly, and if it does the surface isn't very smooth) --- I was sort of thinking that the Carclo would do it for me.

I'll take a look at doing one when I do more dedomes later this week.

I had the same thought about some newer xp-l’s , i was hoping for a miracle :stuck_out_tongue:

I got two XP-L2’s in from Kaidomain (very cool V4’s). I have no time for an emitter test, but I just made a pretty stereo picture at 0.5 mA. And indeed, the phosfor looks no different than the XP-G3.

I checked it in a few reflectors (small OP reflector and smooth C8 reflector) and, as Richard pointed out, the tint variation over the beam is really not as noticable as the XP-G3, they should be fine in flashlights (apart from that they will not dedome well), and if they come in 90+ CRI just like the XP-G3, there is no competition in output.

Just did a current draw test:

  • FET driver w/ XP-L2 V5 4000K on Noctigon w/ HE2 fully charged: 8.2A!
  • FET driver w/ 3x XP-L2 V5 4000K on Noctigon w/ HE2 fully charged: 15.2A!

Better make sure you've got your heat sinking and reflow right!!! These have low vF similar to the 219Cs.

Ah, so that is the deal, low Vf, nice for single cell multi-emitter lights! (if you like output, that is :wink: )

Nice update guys. Thanks. :+1:

Thanks Guys!
The low Vf should substantially increase the efficiency at higher currents even it the LED isn’t actually brighter compared to the current XP-Ls.
You probably all know this, but it will be much easier to make a single cell light that stays in full regulation at 3A+ for the entire runtime (currently very few lights, mainly from Zebralight and Armytek manage to do this).

Very good point. I should have known that, but never thought of it that way. I got my head in the high amps/max output mode most the time, but that kind of usage on 7135 based drivers, for example, is pretty darn good.

Has anyone seen 90+ CRI XP-L2’s yet?

I just looked through the places I know to check and could only find 80cri. Thinking this could make for a pretty nice EDC LED with a bit more power then what I have now.

Well crap, I don’t know why the ones I had died on me then. The remaining two that I had are in route to someone to test…it may have been a crappy reflow?…but it was on two different mcpcbs and they both have XP-L V6s on them now and run fine…so I don’t know.

dj, I'm not sure what was going on then because I have run these very hard repeatedly with no signs of thermal stress. Maybe yours had extra low vF? Did you measure the current draw or forward voltage?

How many lumens you think it is doing at 8+ amps ?

Like 2250-2300( v6 sample, Mouser breed, kit 51), yet it runs hot like hell…i aint quite sure how long how it will hold those on a long term base
G3 isnt much of a high amp long term champ, they die pretty fast( personal exp)

The most annoying is that they dont dedome, thus makes them useless fro throwers

I'm only seeing 1500-1600 at startup OTF, but that's non-AR w/ an OP reflector. 1400+ after 30-60 seconds. I'd believe 1900-2000 LED lumens if you could keep it cool enough.

Nah, I don’t have a very good meter and I’m doing (what I consider to be) “ok” with a meter if I can measure battery voltage, lol. I’ll let you experts handle that end of it all. I probably need to go back to the drawing board and start off with this to learn about current, lol.

I just received a package from DJ :partying_face:

Hopefully I will have some time later today to see what was up with his emitters and get some hard numbers.

I’m going to lean towards crappy reflows, especially if RMM is running one dd with no problems. That just means I’ll have to stick with getting them from RMM already reflowed, lol…which is what I normally do any way.

The reflow may be part of it but a poor mate or a bit too much heat sink compound can be worse than none at all, the stuff’s supposed to fill the gaps where the metal surfaces don’t touch rather than create a film between the surfaces. Extreme current exacerbates the effects of thermal blocks. DTP copper is the best initial step available but that isn’t the whole picture.

If you’ve modded you’ve probably killed a few LEDs, at least yours DJB died in the persuit of knowledge. Every new led throws us a curve or two, the fun is in finding what they’re good or not good for.

I am in the middle of torture testing one of the XP-L2’s at the moment, took a break for dinner.

A sneak peak though. Already at 10 Amps and the highest numbers I have ever seen from a single die LED, VERY impressed so far.

The question is, do I keep pressing it even though I have reached a 4.2V VF until it pops or do I whimp out and call it quits?

:smiling_imp: