Osram Oslon Boost HX

I guess vinh/skylumen found some so we will know soon enough I’m sure

Yes, Vinh and L4P have some already. .5 mm² variant is exciting news :slight_smile:

I could not find the Boost HX on L4P’s website. Vinh definitely has it though. He just posted a pic of it.

Here’s the data sheet for the Boost HM (0.5mm²)

KW_CELMM1.TG

https://www.mouser.co.uk/pdfDocs/KWCELMM1TG_EN.pdf

Well hopefully he provides some test data or can lend a fellow member with the equipment one soon. Very curious if the 4040 Boost footprint allows the 2mm² to achieve the ~5.5A/mm² like its smaller brethren. Or at least close the gap.

Speaking of which, I really wonder how much the rectangular geometry is a functional design aspect allowing the larger die to reach such high current density. Please excuse my lack of knowledge here but is there a flow of current along the surface plane of the chip? Does anyone here have expertise in this area?

No idea really, but if it was all the same, i think we would have many round die power LEDs on the market.

Oh, i thought it was more than 10 % more current for the 1mm², but it makes sense that it will do more for the 2mm²

Well circles, in general, create processing challenges in all kinds of industries. Radii are just harder to deal with than perpendicular lines (again, generally).

I’m coming at this question/idea from a uneven current distribution caused by series resistances. This is the only reason I can intuit - other than tolerance stack up on defects - that there is a decrease in peak current density as dies get larger.

I know older generation CREE leds used to use grid style current spreaders, then they turned into arrays of dots (vias?). I’m assuming those aren’t used anymore with flip chip designs, either that or they just aren’t visible anymore? I guess it’s time I learn me up on some ol’ semiconductor anatomy.

He doesn’t sell them yet, but he said he had samples. And offered some as a prize in the current OL Contest.

The thermal pad is far smaller than any 3030 or 4040 LED.
Its overcurrent performance will be absolutely crap.
There is a reason we are using CULNM1 / CSLNM1 in flashlights and not the CELNM1.
U = 4040
S = 3030
E = 1915 (1.9mm x 1.5mm)
And that’s just the package size, the thermal pad is only a fraction of that.

Yeah the 3030 1mm^2 white flat already beats it in throw, and the 4040 1mm^2 white flat beats the 3030 one.
My CSLNM1 reached 335cd/mm2 at about ~5.5A while the CULNM1 peaked at 349cd/mm2 at ~6A
This was using an LX1330b which overestimates the cd for cool white LEDs, but the point is the relative difference, the 4040 one is best.

0.5 mm² will be good for the smallest lights where even 1mm² is too large. Think Lumintop GT Nano with a shorty tube. That’s what got me excited.
It would also be good in small multi-LED lights, but only for those of us who pick sustained performance over turbo.
You’re right, the thermal pad is just too small and it doesn’t look like a good choice for absolute throw records.

Well, running a larger LED at lower currents will still get better efficiency and sustained performance though…
The smaller LED size would just mean a smaller tighter hotspot.

Sustained lm - larger wins. Sustained cd - smaller does.

I bet max luminance will be right in the same range as the 3030 2mm² (CSLPM1). Yes it’s a smaller package and therefore a smaller thermal pad. But it’s also only a 0.5mm² die. If we look at it a straight ratio of emitter area:thermal pad area, then the numbers are as follows:

[Lower is better, though with diminishing returns]

1mm² 3030 = 0.40
2mm² 3030 = 0.75
1mm² 4040 = 0.16
2mm² 4040 = 0.29
0.5mm² 1915 = 0.66
1mm² 1915 = 1.33

Based on test data from the first three, it’s seems reasonable to expect Boost HM to perform similarly to the CSLPM1 in over-driving situations. One thing to note though is the thermal pad is not centered nor completely overlapping the chip in the 1915 package. Idk what impact this has on thermal conductivity/resistance.

I still think it’ll be a nice option for power conserving throwers at what I predict will be 7-8W max but still luminance competitive with the rest of the white flat / boost line-up.

PS: The binning for the Boost HM seems 10% higher than the HL and they claim 255cd/mm² within specs. Mouser will have 4000 in stock on Feb 10 link

Ah, true.

Hmm… So. How Cree production process can be better than Osram one? I mean XP G2 vs XP E2 family of emitters where older and bigger brother beats the smaller one… Yes smaller is more efficient one but for the lux/candela hunters it never prevailed over XP G2.

I expected same if not better technology from Osram. Where Osram WF1 would act just like XP E2 from Cree offering optimal performance with good efficiency while Boost HX would act as his name says; boosted lux/lumen performance… But as you guys says that may never happen so imho conclusion is that we don’t have any substantial lux/cd improvements even in 2020.
XP G2 is still good emitter comparing to those new Osrams but biggest question of all for me is:

Where did father Cree gone? Highest performing lux/cd emitter is old XP-G2 Come one Cree! Let your CEO starts reading light forums!

The HL (1mmsq) is already end of life, as someone mentioned in another thread.

The HM looks quite interesting, lower rated power at 4-5W (without overdriving, you guys are crazy!) but only 0.5mmsq emitter. Very impressive. https://www.mouser.com/pdfDocs/KWCELMM1TG_EN.pdf

It looks like you can place your order directly with Mouser, too! Who will be the first to try this? Not high power, so I’m still looking for Boost HX, but if you’re looking for a laser spot this will be pretty crazy.

(photo is not correct on this listing) https://www.mouser.com/ProductDetail/OSRAM-Opto-Semiconductors/KW-CELMM1TG-S3SA-ebvFfcbB46-8F8H?qs=wnTfsH77Xs6UbDlfbzhoTg%3D%3D

EDIT: I see Jared already posted this, whoops.

Yeah you’re right, in smaller low power/low cooling flashlights the CELMM1 might be a better choice than the 1mm2 white flat.
More sustained candela.
I wonder what the MCPCB for it will look like…if there are any yet.

Something is not clicking here: The OSRAM link says ’Therefore this LED is ideally suited as a powerful light source for high-definition MEMS AFS.“. MEMS (microelectromechanical systems) AFS (airflow sensor)? Or is there another MEMS AFS?

Similarly to this:
https://led4power.com/product/mosled-extreme-mosx-ceramic-insulation-luxeon-z-es-mcpcb-20mm/

BTW this style of footprint is quite common in automotive LEDs nowadays. I wouldn’t be surprised if there was some board available.