They can be driven with 30mA at up to 45°C temoerature (at the solder points). This should never be exceeded at night, hotter climates.
I would go with 25mA just to be safe.
Overdriving them is a very bad idea! They will die much sooner because the heat has nowhere to go. I think there are some tests on this on CPF.
I’m in for one warm-white and three cool-white.
I’m interested in two 3200K and two 5600K 
Thanks to all involved, this seems much more likely to happen now :+1:
I was on the list for two of the mooted Fenix version, but with Sofirn aiming for $6, I can put the same money in for twice as many lights!
I strongly recommend that the LEDs only be driven at 20mA.
We’re trying to build a bulletproof light here, and that’s the recommended spec from Yuji. One of the best ways to make electronics ultra-reliable is to run the parts well below their maximum rating.
If I had this project on my lab bench, I’d even be experimenting with 15mA, on the off-chance that the light output might still be acceptable.
Regarding the three colour choices, I’d suggest: hard-anodised black; hard-anodised grey; and red.
Black because many prefer an unobtrusive option; grey as an option that’s easier to find in the dark, but can still be hard-anodised; and red where high visibility is the priority, despite the slightly less robust anodising.
Yes it does matter. Impacts cause extremely high G loads. Solder is not a particularly strong material at 1000 G. The robustness of the E01 is legendary and there have been many tests of it against other unpotted 1xAAA lights. It always comes out on top.
I agree with Parametrek about potting the light.
It’s very important for impact resistance, and it can also help with water resistance in the event that an o-ring fails.
I’d also like to see a spring on the driver board to cushion impacts bouncing the cell around, even at the price of an extra couple of millimetres in overall light length.
Interested in one of each tint.
As I said, I’m skeptical and like testing. There clearly is a correlation, the E01 is robust and the E01 has a potted driver, but that does not neccessarily have to be a causality. Solder is not strong but perhaps way strong enough for this, 1000G sounds an impressive number but a soldered tiny coil may survive 10,000G, who knows without testing.
So the “yes it does matter” still needs backup for me to accept it, either by experiences from small flashlight users, or actual impact tests of electronics showing mechanically failing components.
Size is not the most important feature of this light. It should be bombproof. So nice thick walls and a few mm for a spring is not a problem.
I wish one could upvote posts. I’m saving this as an example of rational thinking to show to so many people I encounter in real life.
It is likely a good idea to pot the driver, and a short stiff driver spring may be a good idea as well.
But I hope for actual data to back ideas up.
Over the 6 years I have been on BLF (and CPF), I have encountered many many flashlight myths, a lot were tested and dismissed very easily, a few were actually true, and some were too difficult to test. I dislike developing flashlights with unneccessary build-in BLF-myths.
Wow Sofirn is really doing us a huge service here. Even if they sell, 100 of them, that’s only $600, which is much less than the tooling and setup required to make a new batch of a new flashlight. I bought my E01vn Yuji for $48 from Skylumen.
My Yuji 3200k tint is better than typical Cree 3000k, which are more yellow/green. However, my 219B 9050 3000k has better tint than the Yuji even if the Yuji has higher CRI because 219b is closer or even below the BBL whereas Yuji tint is above the BBL.
I do wish Sofirn can make flashlights using the Optisolis or E21A emitters. Optisolis is very cheap if they buy in bulk and suppose to be as close to simulating daylight as LED tech allows.
Some considerations:
The Optisolis is very difficult to make into a decent beam, just very diffused it looks ok.
The E21A is difficult to center, you can not have a centering piece in contact with the led or it will be damaged.
The Yuji 5mm leds on the other hand produce a very nice symmetrical beam, without optic or centering issues. In use it is a very easy led
Potting helps with robustness, but not just in the way mentioned here. Small components will probably never break off. If mixed with suitable materials it can help keep the driver components cool. This is not important at these low power levels though.
The most important thing to fixate would be the wires going to the LED. They are usually the first thing that rips off on impact.I would also contact the battery with springs on both sides. That increases robustness and the light doesn’t turn off momentarily when it falls down. The design of the Thrunite Ti (I own the v2) is very bad in this regard. The didn’t use a real spring in the head, the contact piece they use can break after little useage.
Three warm ones for me, please! :+1:
I hope it can tailstand with a keyring or lanyard attached.
I’m looking forward to watching the development of this new high-CRI cockroach. :partying_face:
I disagree, I think size is very important, it is one of the key features of the E01 that it is that small. And apparantly a light this small can be very robust without having those thick walls.
That said, I fear that I sound very dismissive in my recent posts and I may have too strong ideas about how this light should be.
The discussion has turned to if potting is helpful in small lights. ReManG did a drop test in his review of the Manker Boney, after some 20 drops from 5 feet to a concrete floor, the light failed. REVIEW: Manker Nichia AAA Keychain light aka "Boney" PIC HEAVY - #14 by ReManG
That failure was the perfect chance for him to open the pill to investigate the problem. In this thread, in the 5th picture down he found a wire had broken from the board. Cracking open a Manker Boney LED pill 7+ DAYS on 1 fresh alkaline/Component pics/ Mhanlen verified 7 day run time@ 1 Lumen +/- His thought was the wire was the heaviest driver componenent on the board causing it to break off.
On these small lights with no lens the LED is exposed to the elements, my fenix EO1 worst torture test for it is, the potting may help with waterpoofing becausr it has suvived 3 trips through our clothes washer.
Also I want to say thanks djozz for your effort in making this closer to being a finished product.
I can help with the list, as well. Maybe there should be a team account so a single list can be maintained?
I’m very happy to hear they’re confident they can achieve similar performance to the E01 driver.
I mentioned the possibility of a 30 mA drive current as a suggestion to discuss, but I’m reluctant to push Sofirn to make design decisions they’re not confident in, especially since we’re only talking about going from ~8 lumens to ~11 lumens. Others also had a good point that the goal here is a bulletproof light, so we want to be certain over-driving does not compromise that.
To clarify something, Yuji specifies the output of the 5600K version as 6.6 to 8 lumens, and the 3200K version as 6.1 to 7.5 lumens at 20 mA. The output curve in their datasheet indicates 30mA should produce just over 1.4 times the standard rated output.
Just my opinion 
. Maybe I should put it differently. It will not be a dealbreaker for me if it’s a bit bigger than the E01. But I for instance still like the old kd buckle v6, so maybe I am not the best reference.
in for 1 of each please
I’m in for 2*3200K and 1*5600K
In for one of each please