Led4power.com : LD-4 CC linear drivers, ILC-0/1 illuminated tailcaps, optics, MOSX, copper DTP MCPCBs...

Thanks Hoop, nice info.

Can’t wait to get mines !

I forgot to put my old test results:

I calculated/estimated lumens from my lux numbers and datasheet bin specification.

Yellow marked lumens calculation are based on old black flat measurements at 1A as reference (made by koef3 I think), non-marked lumens are based on ~middle of bin lumen number at 1A from datasheet (330lm, actual middle is 335lm).

Using yellow for calculations….
If this emitter really has 1.0609 mm² and 952 lm we’re at 285 cd/mm².
Note that according to package drawing in the datasheet this LED is 1.0609 mm² minus rounded corners.
Also note that the Blackie HWQP while nominally 1.0609 mm² minus cut corner was measured at 1.12 mm².
I tried to measure the size based on djozz photo, but haven’t really arrived at satisfactory numbers…

Assuming that it actually is 1.0609 mm² it is much more efficient than the previous generation (in terms on intensity vs. efficacy). I’m really anxious to see a Koef3 test where I can compare it with the competitors directly…

That’s what I’m seeing, note that I’m far from fully trusting the chart.

Interesting point:
I still think there’s something that we don’t understand about Synios. If we add it to the chart with intensity that can be calculated for a Lambertian 0.503 mm² emitter, it looks like this:

Likely coincidence though.

My son and and a friend who was coming to play at our place had way too much energy so I kicked them onto the streets to play in the playground a few streets away. So that freed some time for the led test.

Note that I used my standard test method with all the added disclaimers about how it is done. Especially note that I keep using the djozz-lumen although I know that it is between 7% and 10% too high, I do this to be consistent, so results can be compared to all my earlier led tests.

I used a DTP 16mm led4power board for reflow because those pads matched the smaller Oslon pads of the led just a bit better than a Noctigon. And indeed the reflow went easy.

As I noticed before my maximum is at a lower current than other testers, the cooling seems less well done in my set-up. Part of it may be that I usually apply a generous amount of solder during the reflow, a bit more than the minimum needed (with Oslon-sized leds on 3535 boards, excess solder can not be squeezed out by tapping on the led). This results in a somewhat (not much though) thicker solder layer that may add to a slightly higher thermal insulation of the led.

I stopped the test at 7A. The led emitted angry blue light then, but I kept it 2 minutes at 7A to see if it could handle it, and it did. Afterwards I turned the current down to 4A and kept it there for half an hour, the output was only 1% less than the initially measured output at 4A, so the led seemed to have handled the 7A maltreatment with no problem.

:open_mouth: amazing.
ahaha look at that poor xp-e2 :stuck_out_tongue:

Thanks for the testing guys!

So in the end the lower Vf is probably why the performance is better. It simply has to deal with less heat at the same current.

What die features determine Vf? In other words: if you want your LED to have low Vf, what do you do to achieve this?

I only know that flip chip LEDs have a lower Vf. Presumably because the resistance of the current spreader is much lower (it replaces the bond wires). The remaining Vf is caused by the actual led junction. It is specifically for blue LEDs (red LEDs for example have a lower Vf). There are probably additional factors which I don’t know about.

Also, die size is a factor. You always need to compare LEDs with the same die size (current density). That will show you that the XP-G2 is really old technology.

Osram UX:3 LEDs like the ones above use vertical current spreaders (the little dots) to distribute the current more evenly.

We are getting really off topic here…

Can you set samsung price for 100?

Lower VF is good not only for lower temps (and more output) but also higher efficiency and longer regulated runtime in single-cell lights.

I hope that one day LEDs have a low enough Vf that they can basically run at full power until the battery is drained without the need for boost circuitry.

These CSLNM1.TG are 100% the best thrower LED in existence, I highly recommend people buy it :slight_smile:

PM sent.


thermal path definitely looks not optimal, I got peak at 5.75Amps. Excess solder could cause that when power density is high like with this LED. Also, I'm using lead-free solder which has a little bit better thermal conductivity.

I have been noticing this since other people started led tests, so it is good to have more than one test of the same led. My not so ideal heat-path tests could be seen as a simulation of average not so ideal flashlight builds :wink:

FWIW, the X6 build is indeed using the Ledil Iris, in the XP-E optimization.

About to go build my newly arrived purple Convoy S2+, with a 12A L4 and 3 LH351D’s at 80 CRI 5000K on Hoops copper pill. Should be an epic little tube light… :smiley:

That sounds dangerous. :slight_smile:

Crossing my fingers hoping that heatsink threads in, haha.

Heatsink fit fine, all went together very well. Used the small/large combination of Blue’s springs on the tail switch board and a single small spring on the driver, 20 ga Teflon leads to the triple Noctigon. But even on a 30Q it’s “only” making 2600 lumens. Not sure why that is, will look into it some today.

The Samsung’s make a huge flood of hot spot with virtually no spill, no artifacts, pretty nice triple, great for a walk or relatively close work. I have a blue S2+ also with Hoops pill and it’s making 3029 lumens with XP-L V3 3C emitters. So now the pair are pretty neat. :smiley:

Oh, FWIW, I reflow solder the triple Noctigon onto the copper sink/pill. :wink:

AND, let me say once more… Hoop, these pills are stunningly beautifully made! Really nice using already perfectly executed components and simply assembling the light. (I, uh, DID actually put the positive on the driver wrong and had to troubleshoot that, white Teflon intended to be to positive, white with brown stripe intended to be negative, got em reversed. UGH! Like this is my first rodeo…)

Did you enable direct drive in the firmware? By default it’s set to CC for the highest mode (12A max)