Looks identical to Luxeon T,but lumen numbers are improved,BUT there is L1T2-5085, *85CRI minimum 5000K* version with 102lm/W@1000mA,85C ;)
For max. lumen output there are 70CRI min. versions in 5000,5700 and 6500K with 160lm/W@350mA, and 130lm/W@1000mA,85C.
So basically,
L1T2-5070 is equivalent to XP-G2 *S3*,but is 70CRI minimum,5000K,better thermal resistance,lower Vf.
L1T2-5085 is perfect nichia 219 hcri replacement,but with higher CCT(cri is probably around 90,close enough IMHO),much higher eff. and possible lumen output from single emitter,much better thermal resistance,much lower Vf.
Nichia 219 have a high Vf and not are not really 1 cell friendly, not only that but one of the highest thermal resistances for it's size typical 7W/C and 12W/C Max.
Example for Vfs based on actual tests by different advanced users not based on datasheets.
Nichia 219 highly appraised one:
3.886V at 2A
Cree XP-G2 R5 criticized one:
3.25V at 2A
Now for 1*18650 cell you start with 4.2V which is surely limited to less by sense resistors, springs and all that.
Lower Forward Voltage (Vf) is better for many reasons. Off the top of my head, and in no way technical, longer run times and the battery can maintain the required voltage longer, and it also typically means lower power required (unless the current is higher than normal).
I measured around 3.30Volts at 4A for Lux T and Z ES on alu sinkpad.I’ll try to solder one T and one Z ES to xm-l copper sinkpad,and compare it with xp-g2 on copper(volts and ceiling bounce).
Just to be clear what sources I used for the Nichia and XP-G2 LEDs, CPF and Match
I just took a XP-G2 R4 on an 16mm by 1.0mm aluminum PCB and measured 3.060V at 1A, for 2 seconds because I didn't want to get too warm, ambient temp 21C.
They are available for some time (mouser,digikey).
Some more info on testing(I'll put more graphs later):
Xp-g2s R5 1A(FT) mounted on noctigon copper,luxeons on ALU sinkpad-Z ES are warm white 3500K 80CRI,and Ts are 5000K 80CRI.Why these?Because they were first available at the time. Not sure does different phosphor layer has some impact on overdriving capabilities(all tests on net are done for top binned cool white leds),but i assume there is no impact.
I also soldered one Z ES on copper sinkpad(not sure how successful this was, for now) . Stars are mounted on 90x30mm round polished alu heatsinks(AS5 paste).
I actually dedome lux T(easier to solder).It's a weird led.It has core identical to Z ES,around this core is alumina frame(white stuff),and silicone dome hold parts together.But there is bad news-dedoming(gasoline) removed some phosphor(just like mt-g2),and color became cooler.Since Z ES is already undomed,dedoming lux T doesn't make sense,but more testing is needed.
Voltage was measured with UNI-T71C , kelvin method(4 wire),so voltage readings should be pretty accurate.
I also did some ceiling bounce readings,but I'm not sure how reliable they are.Max reading (xp-g2@5A) was only 85lux,so resolution wasn't good.When you consider that xp-g2 is 1A tint and 70CRi typ. and domed,while luxeons are neutral-warm white 80CRI dedomed,possible error is huge.Nevertheless,some data is better than no data at all :)
Some data for xp-g2s:
-they die at 5500mA(with one gold wire at 3500mA)
-their voltage varies quite a bit(upper graph for xp-g2 is average value of two leds,one had 4.02V at 5A,other had 4.22V)
-no difference in Vf for domed vs. dedomed (I got higher voltage after I accidentally broke one gold wire,so higher voltage after dedoming means you probably damaged wire)
-next thing is weird:lux drop after dedoming was negligible??? (my only explanation would be that more blue is converted to green,and green gives much more lm/W,so efficacy drop after dedoming isn't big as it should be)
