Future development of the maximum luminance of LEDs

Yeah, but with optimized electrical path and a CC FET driver you will have the maximum output for quite a while.
Run it at 4 - 4.5 A and it will be longer with probably not much less output.
Is there a test of this LED on the forum yet?

Didn’t know (or remember) the Aspires sagged that much though.
With cheap springs you can apparently get away with it.

It looks like it starts at 3.7, but at the beginning it is close to 4.2 like all other batteries.
The surge current happens when the circuit is first closed, and this initial spike in current is what will blow an LED in the first few milliseconds.

This could be due to smoothing of the graph though, i was told the drop is instantly when i asked about the same phenomenon.
A large enough capacitor over the driver input could solve such problems though.

True, or an in-line inductor.

Hey, you said you saw a test of this “Flat White” TG somewhere.
Do you have a link?
Wondering if it’s useful to run it over 4 Amperes.

Depends on cooling.
The Driver had his black flat running at 4.5A in his xcalibur, and he had some graph showing how the output drops to 75% after a few seconds or minutes.
I got output increases to about 6 amps on my black flat because I was cooling it with a fan cooled CPU heatsink and liquid metal.
The CSLNM1.TG is basically just a better black flat as far as we know, so I would assume it can also do 6A or even more with appropriate cooling.

From 3.3A to 6A it has performance variation of cca 30%. Above 6A it starts to drop in simple aluminum flashlight host.

So logically with better cooling it gotta perform better.

I did not get cherry picked Osram White emitters either. So 10 % lux variations are possible like with any other emitter.

I’m going to buy a DPS5020 immediately so that I can actually test the LED at high currents :slight_smile:
We’ll see how hard we can push it.

That would be nice… :beer:

I would never go to 6A with passive cooling. The center of my Black Flat has started to slowly turn black at 4.5A!

A soft start turbo would pull the cell voltage down before going 100% fet.

Say I would like to solder a coil inline with the one of the ledwires to dampen the surge voltage, what value would do the job?, would a coil recovered from an old buck or boost driver come near what is needed? Same for a cap across the ledwires, what value would work?

Also posting this here, so it may reach more people that are interested.

I just put the new OBF successor in my BLF GT Mini. The max I measured was 282k cd. But with a protected battery at 4.1V the current is already at 6A at the tailcap. I’ll see if I modify the firmware to reduce the max output to 80% PWM. But the LED scaled all the way up to 100%, so I’m wondering what the actual limit is.

Even at 3.65V battery resting voltage, I get 260k cd. So it was probably overdriven a lot.

Beam looks like this. Ideally the 2 rays limiting the hotspot should be parallel right?

Nice… But please add which battery did you used…

This emitter is like Viagra it doesn’t fall in performance :slight_smile: It will perform with 6A and 3.3A :wink:

Keeppower 3500. So a protected GA

Did you used spring bypasses?

No stock GT Mini. Double spring in the tail and single driver spring. With bypasses and low RI cell I can easily see this pull 8A at least. :sunglasses: Boom!

I guess that Panasonic GA is ok if it will not pass 6A mark in DD setup where this emitter starts to loose performance…

I tried this low current cell: LG 18650 BD1 (pink cell unprotected) and since that is 4.35V cell charged to 4.2V it did not passed 5.5A with Osram white so I guess if charged to 4.35V it would not pass 5.8-6A but I don’t have 4.35 charger to test that.

Edit: Linear driver should be better choice.

BTW BOOM! Will not happen at 7.2A… Tested with Samsung inr 30Q(real Samsung cell from nkon.nl) … And I really doubt GA can reach 7A mark even with bypasses. Let me check… Yes in my test performance at 7.2A performance drops for cca 20%

I got a VTC5D sitting here. :smiling_imp: Nah I’m not gonna blow the LED up. I really love the light!