Nichia 144A and 229A series: bigger dies, more output, 90CRI included,.......but no thermal slug :-(

Barkuti, pretty sure an animated smiley flippin the bird is in direct violation of forum rules on profanity. You might wanna check that…

Here’s where I get a little confused with electrical arrangements in LEDs.

A common 5.6mm laser diode-can, can be powered over the ground pin, which is sometimes (-) and sometimes (+). As an example, 405nm diodes use a boost driver, 18650 for power, and the body would be negative just like a flashlight, with a diode vF of 5-6V. OK, it’s common practice to solder the negative and ground pin together on the same wire, positive pin on other wire of course. Clearly the driver still has to complete the circuit for power to flow. Why can’t an LED resolve the same outcome? Where negative could be your DTP. :question:

Anyways, I would certainly love to try these two LEDs. It’s incredible what the 219C is rated at on the spec sheet (326 lumens, I think), vs what it can actually output. Just think about the possibility of the other two then, when cooled correctly. The 144AM rated at 1300-1400 lumens at highest bin; I could only imagine a single mono die LED with moderate CRI potentially unleashing 3200-4000 lumens under a smooth reflector.

In the meantime, are they seen for sale anywhere? I would not mind doing an output test on a home-made copper board, like I did for the Luxeon Z test.

A little more 144A info:

- Emitting area: 4x4mm (16mm2) - same configuration as a XHP35 (with lower forward voltage)?

- Aluminium Nitride substrate (285 W/(m·K))

  • Gold contacts

Alumininium nitrite looks like the way to go creating a board for mounting these… it should be reasonably cheap to have someone make a bunch of 16 and 20mm disks… then glue two pieces of copper sheet to the top to act as electrodes. Done.

Welt Electronics sounds like one possible source.

That’s more like an XHP70 actually (which has 2mm² “XM-L2” dies), yet made as a monolithic die of course without the spaces. :wink:

That would be good! XHP70-like output, no window frame=no donut hole.

If we’re talking about what-ifs, this company is placing Cree dies into cylindrical LASER style cans! (I can find the company again if anyone actually wants to know who.)

Of course I would still love to know the reason why negative could not be body-grounded for heatsinking if positive was isolated. :slight_smile:

Already made several MCPCB specially designed for this one! You can crash test the LEDs and the MCPCB (I got several CCTs) after Maukka spectral tested them all ;)

The samples took off the factory in Japan in 160829. Don't know how long until they get here.

I created a thread HERE (copied from my thread in CPF), because I didn't know you did it first Worth take a look for some comparison with popular CRI90 Crees. Well, at least spec by spec in the high 90CRI domain, it's superior than comparable XHP50 (colour and performance).



Most, if not all, flashlight led drivers regulate the current to the led by the low side. This means the led's positive lead is directly connected to the battery anode, and its negative lead goes down to the driver, while at the same time the flashlight body, and thus the led's thermal pad, is at battery cathode potential.

And this is the solution, for y'all to see:

Installing the batteries in reverse, we would set the thermal pad and the led's positive lead at anode potential: both leads can get unified. In this way, we would only need to isolate the led's negative lead to the driver. However, this requires a slight led driver PCB redesign to shift their boards polarities: battery cathode connected from the underside central pad, anode through the driver sides/pill and, well, through a positive wire coming from the led MCPCB (lower resistance connection, fellows).

Did I put my foot on someone's mouth? Where's my prize?

Cheers ^:)

We would have to know if both pads are doing the heat transfer to the star.
if so, one could solder the LED on 2 half circles of copper and then put electrical isolation between it and the pill.
That way you have direct thermal path to the star and a big surface with maybe kapton film and some goo on the star.
This way you can avoid the fuss of re-designing the host flashlight.
Just learned that 90% of the heat transfer is through the cathode.
But i think it’s a good option to isolate the star from the pill, not the LED from the star.

Most of the heat generated at the cathode side. I made my design according to Nichia’s suggestion: Here

BLF Member djozz has some very nice non-DTP boards for the Nichias without thermal pads. He had some made so he could test out his design with a new MCPCB manufacturer that showed up here a while back. He’s selling them now, at cost. They’re $2USD each. Look at his signature line for a link to the thread.

I think that clemence’s board, that has direct connection to the core on the cathode side, should perform better than my boards, but of course when these leds arrive I will do an attempt to test these boards directly against each other with the same led. :slight_smile:

Hmmmm, I think I have to send Maukka one extra NV4 for you to test. I have several 6V NV4 @ 6500K; R7000; D1200 rank, that I’m not interested at all. A perfect guinea pig for the dead match.

Long before electrically neutral thermal pad introduced, all LED designed that way. Miniaturization and higher LED wattage has change the norms. But when space is not the limitation, non thermal pad LED and non DTP board usually cheaper to produce.

Well, I don’t know what his design looks like, but I was thinking that electrically connecting the LED- to the board makes the whole thing useless for 99.99% of flashlights, because the driver regulates current on the negative side. Then ‘grounding’ the negative side of the LED makes the light single mode Turbo only! :open_mouth:

…so we should electrically insulate / isolate the MCPCB from the pill with a thin layer of something plus some thermal goo.
Should i make a crude drawing?

The current sense feedback is on the negative side of buck/boost drivers, to my knowledge. This is baaaad news. For the love of g0d, why have those @#$%ns chosen the cathode slug as the main heat sewage? They just weren't thinking in flashlights at all, which I can understand, but it could also have implications for “integrated” drivers.

Of course, just an opinion. Time for BeO/diamond dielectric MCPCB's fellows.

Cheers ^:)

My MCPCB is designed for prototyping purpose. It will accommodate various optics and mounts - that’s why it’s big and thick without pre drilled holes. The design makes it easy for various testing, I can mill it down to circular 20mm or any shapes without risk to short any electrical traces because it’s shorted anyway.

To make it electrically neutral is EASY. You just put any commercially available dielectric tape/epoxy/glue between the MCPCB and the host. The heat concentration already spread to area 95 times the cathode size, less delta T. Even if we use dielectric material with only 3W/m.K (thin layer of course) thermal conductivity would still theoritically superior than those LED with thermal pad. The cathode makes metal - metal contact through copper and solder connection, less thermal resistance than through dielectric - solder connection from the LED thermal pad base. Unless the base of those LED with thermal pad is made from material with thermal conductivity superior than copper this design would be better for high power LED. But I can’t be really sure until mr Djozz done with his back to back test.

The best test is to compare it to XHP50 with equal sized DTP board.

I can add the XHP50 test to the graph for comparison :slight_smile:

The package is on the way to Maukka, should be there in a week. I added extra bare NV4 emitters from each type for you. There are total 13 emitters including 3 pcs NVSL219CT R9050.


  1. NV4W144AME (6V) - sm653E1200KR70 - 1 pc

2. NV4W144ARE (12V) - sm575E1000Lv9R9050 - 1 pc

3. NV4W144AME (6V) - sm575E1000KR9050 - 1 pc

4. NV4L144ARE (12V) - sm305E900Lv9R9050 - 1 pc

5. NV4L144AME (6V) - sm305E1100KR8000 - 1 pc

6. NV4W144AME (6V) - sm653E1200KR70
soldered on VirEnce DTP MCPCB - 1 pc

7. NV4W144ARE (12V) - sm575E1000Lv9R9050
soldered on VirEnce DTP MCPCB - 1 pc

8. NV4W144AME (6V) - sm575E1000KR9050
soldered on VirEnce DTP MCPCB - 1 pc

9. NV4L144ARE (12V) - sm305E900Lv9R9050
soldered on VirEnce DTP MCPCB - 1 pc

10. NV4L144AME (6V) - sm305E1100KR8000table(table#posts).
soldered on VirEnce DTP MCPCB - 1 pc

11. NVSL219CT - sm305D200L1R9050
soldered on SinkPad DTP MCPCB - 3 pcs


Thats a lot of work to test^ but can’t wait to see them!