Ðirect questions on LEDs directly from manufacturers through me(ENDED)

Flashlight Modding and DIY Parts
1

So, guys, as many of you know, I’ve gotten a job at a lighting manufacturer, so I have direct call access to these LED manufacturers:

- Cree

- Luminus

  • Samsung

I’m able to call them directly and ask for information they weren’t willing to answer in ANY of my emails at all. They wouldn’t respond in any other way.

So, I have had some questions answered these last few weeks, and since this is the last day at my job, I will try to get as many answers as possible.

Some beginning info.

1. SST-40: Luminus changed the manufacturing process at some point for the SST-40.

Basically, the earlier SST-40s were using pure gold wires, as it was easy to manufacture into very tiny bond wires, so no new equipment/supplier was needed.

However, to reduce costs and to boost reliability, they switched, rather recently, to gold plated copper bond wires, which enabled lower temps, lower costs, and most importantly for us, higher driving power.

2. SST-20: Luminus is actually thinking about releasing a 5000k 95CRI SST-20, if there are enough very large clients wanting this. Not the case currently.
Also, about that SST-20 FD2 and FA3 tint bins, they are actually 2-step tint bins, which is why they are in very high demand, even from flashlight manufacturers.
Apparently, 2 China OEMs are ordering absolutely massive quantities of them, one being a lighting manufacturer, the other being a distributor for flashlight LEDs. One of their clients is Mateminco.

3. SBT-90 Gen 2 vs the Gen 1: Still a very new LED, so no details could be spared. The only things that I could gather was that current handling was improved, phosphor quality is higher, and bins are of much higher quality vs the Gen 1.

4. Domeless XHP35HI.2: Apparently, yields for good domeless XHP35.2 HI aren’t good enough yet for the brightness bins to be fulfilled adequately.

5. A 3V variant of the XHP70.2: no chance. Required current is too high for the customers.

6. XHP50.2s in other tint bins: will come with better tint bins, as customers want better color high power density 3V XHP50.2s.

If you have any questions, ask them quickly!

I’m serious.

2

Well, the big question for Luminus: will there be 95CRI warm versions for the SST-40 at any point?

3

1. Will there be 95CRI warm version for the SST-40 at some point?
1st question to ask. That’s a good one.

4

Ok give me 5 minutes. I’ll call Luminus.

5

Does Cree have any plans or even thoughts on domeless XHP50(.2)/XHP70(.2)? Does Cree care at all about improving tint shift vs. emitter angle? (XP-G3 is unusable without a floody TIR, etc.). I basically don’t have use for Cree emitters at this point…

6

1. SST-40: There will be a 95CRI version of the SST-40. Initially, as with the SST-20, there will only be a 95CRI of 4000k CCTs and below.

2. Domeless XHP50/70: there have been requests from manufacturers after other LED manufacturers started releasing domeless large LEDs, like the CFT-90 Gen 1/2, Luxeon MZ, etc.
The highest probability of there being a domeless XHP emitter would be the XHP50.2, as its small die size and high power density makes it attractive for high power long throw applications(not my words).

Any other questions.

7

Thanks for the information (feels like I’ve been to a fortune teller :party: ) , then the wait for high CRI SST-40 continues.

8

Hey mate i have a question not directed at manufacturer in particular but seeing as there is no official documentation on this.

Resting a reflector or optics directly on a LED? I have seen a bunch of light released that have a reflector sitting on the edge of the LED is this bad? (we know its bad). How much downwards force can be applied to a LED? What are the dangers of this practice?

9

Questions for all three of them:

Are any of the manufacturers interested in making a higher power and/or higher CRI version of 3mm and 5mm leaded “high brightness” LEDs? They don’t need to be super cheap.

Higher Power: AFAIK, the top current rating is 120mA for 5mm and still 20mA for 3mm. It would be nice to see those numbers bumped up with current technology. There are plenty of possible applications for these if somebody would make them. I would personally buy a bunch of them, but I couldn’t buy enough by myself to justify a custom order.

High CRI: Yuji just quit making the high CRI ones, so it would be nice to see one of the major emitter manufacturers step into that area. BLFers would eat these up, I’m sure. And there are still other lighting applications where these would be top choice. Photography lights and store display lights come to mind.

10

@everydaysurvivalgear, if I want understand well, it can be done that way to optimize focus, but it is recommended to use a very thin sheet of plastic/silicone to protect the LED substrate.

It’s not actually recommended though, even with a plastic reflector: the LED manufacturer(specifically Cree here) does not validate LED warranties if the substrate has been damaged by a part, if the LED does not work anymore.

@DavidEF, that was quick, for Cree anyway(still have them on the phone actually)

1. No.

2. No.

3. No.

Almost all manufacturers of small luminaires use 5630 LEDs, not 5mm LEDs.

11

Nice. The sst40 hi cri was my main question also. Maybe worthwhile asking the others also if a 5x5mm hi cri led is planned.

12

At Luminus.
Do they plan to release also a high CRI version of the SST-70? Is the led 5050 foodprint?
At all 3
Do they have any plans to release a led with a round die like the SBT-70 in the future?

13

1. They can’t give me any more details than you’ve already got.

2.1. Cree: No.

2.2 Luminus: No direct answer, which probably means yes.

2.3 Samsung: No.

14

Guys, I only have 30 mins before I go home, so ask any questions you have lying around.
Last day at my job before university comes back.

Some questions I got answered:

1. Are the rated lifetimes like L70 performed on aluminium MCPCB or copper DTP MCPCBs?
All of them: All testings and ratings are based off of lab temps using aluminium core PCBs. Although copper core PCBs perform much better than aluminium PCBs at max rated currents, we do not give warranty to OEMs who overdrive LEDs because of temperature concerns, along with high thermal resistance on the thermal interface material and heat dissipating part. However, to be truthful to you, this is why we give lifetime/temperature curves to OEMs so they can get warranties according to the specified temperature in their product. Some high performance OEMs to use aluminium oxide MCPCBs.

2. Is there a plan to make a 2P2S/4P1S XHP35HI?
Currently, no.

3. Is there a plan to release a domeless SST-20?
There was one. However, the current brightness bins of the SST-20 aren’t high enough to fulfill the theoritical binning of the brightness characteristics.

4. At what level can we interface with the company directly?
Cree: 10000pcs+ in the US.
Luminus: Whatever your distributor can’t fulfill.
Samsung: 50000pcs+.

15

CREE with only 10,000 pcs? I thought it was much higher than that.

BlueSwordM, Since none of them have any plan to release a higher powered or higher CRI 3mm or 5mm leaded package LED on their own, I’m now wondering just what the MOQ would be for a custom request to do just that. I know I can’t reach it myself, but maybe it can be done with some organizing. :money_mouth_face:

16

I never said that about a custom request.

A custom request would probably be in the 100 000-1 000 000 PCs range.

17

Can’t wait for the high CRI SST-40. My H03 is begging for one of those! Thanks for the info, lots of this is very interesting.

18

Wow,
Thanks for sharing all this with us! I appreciate the extra effort you put in to benefit all of us.

Maybe some time in the future you can share with us about the time on your job. I wonder how are the industries’ interests compared to a small enthusiast.

19

Luxeon V and Luxeon V2 high CRI would be interesting to me

I guess you dont have Lumileds or Osram contacts?

20

Ok, I managed to squeeze in 3 last questions before the end of my last day, 2 from Luminus, one from Samsung.

1. Will there be 5700k 95CRI COB LED for direct lighting purposes?

Yes, there will be. It’s not listed in the datasheet yet, since demand is rather low.

2. Will there be a multi-die 5050 sized LED for better efficiency and higher voltage?

Yes, but currently, can’t speak more about it due to trade secrets(her words).

3. Samsung: Is a domeless LH351D in the works?
No, but many large clients have requested large special production runs, since they have found by laboratory manual testing that dedomed LH351Ds feature exceptionally low tint shift, even across hundreds of single chips. No timeframe given.

There, ended.