Crash-testing a XM-L2 and a XP-G2 on copper Sinkpads

those are some really interesting numbers - sinkpads go along way :slight_smile:

Thanks you very much for this info. It was exactly what I have been looking for. I’m planning to spend next months flashlight budget on direct copper bonded emitters and I really was interested to see how far I could push them and at what point I would see diminishing returns as well as failure.

Excellent information and timely too. :slight_smile:

Thanks for starting the next round of discussions and for the effort in doing this for the membership. Cheers.

Excellent work djozz! Looks like direct-bonding emitters will allow 6-7A drive for flashlight use. I’ve had a few running in the 5.5A territory with no issues. Looks like the die itself is very safe.
Anyone got (access to) a wire-bonding machine? J)

I sold mine a few years back. It had a really nice microscope on it…

Would be nice to rebond dedomed emitters for 8-9A operation J)

Thanks djozz for the information!

I've resoldered a XPG2 die back onto the substrate, but never tried to mess with the bond wires...

Care to try an XML? I wonder if the three wires will raise the ceiling……

Why are your PS and DMM voltage measurements off by a volt?

Nice testing, thanks for your efforts! :slight_smile:

What an experiment. I am more confident to do 3A for XPG2 now. Thanks.

Awesome test! Very informative djozz. I wonder what would happen if you stuck a piece of dry ice under the heat sink :o

holy cow.

Yes.

Tonight I stuck an XPG2 neutral on a Noctigon inside a Sipik 68. I replaced the driver with a Nanjg 105c with 3 extra regulator chips attached for 4 amps total, running on IMR 14500.

It’s bright, but unfortunately, the focal length is wrong for the new star. I’ll need to file down part of the outside of the pill in order to make it focus properly.

As said, the volt reading of the power supply is a bit wacky, in the video it is too low for a while when the actual voltage is higher, then suddenly starts displaying a correct voltage for the rest of the experiment.

Whoops, sorry missed that part. :slight_smile:

Nice. Thanks for sharing. Looking forward to graphs…
I killed an XP-G2 yesteday. Mounted on 20mm Sinkpad attached to a large piece of aluminium. It was de-domed. About 5A and it was dead. Instant kill… :stuck_out_tongue: (no worries only a cheapo CW from FT)
Im pretty sure others have used them at that current. Id guess my de-doming job had weakened one or both wires (a bit strange since I don’t touch them and never had issues with de-doming in the past).

I have a driver (from STL- V6) that I can easily resistor mod from about 2,8-5A as I wish… Modded it to 4,7A yesterday, but did not to dare try it on an XP-G2 after I had fried one at 5A with another driver. Dialed it down to 3,7A just to keep it moderate. 0:) Im already feeling inspired to go higher now… J)

Do you think emitters are killed more easily if they go from cold to instant high amps? Im a bit surprised they managed all those amps, especially the XP-G2.

Do you feel like doing MT-G2 if you get some funding from several members?
Ill donate 2,5 bucks for the sake of science (killing and MT-G2 and getting some numbers out of the process). Im sure some other members would contribute too.
Or maybe just contact Hank (IOS) and see if he is feeling generous. 0:) Worth a shot…

What do you mean by cold? 20-25C (room temp) or 0C. You want to thermally shock the LED?

Room temperature…

I wonder how an LED like the Luxeon T would perform on a Sinkpad board.