Lume1-FW3X: Constant Current Buck-Boost & FET Driver with Anduril1/2 + RGB Aux

Hello all,

I hope everyone is doing well and staying safe in the worldwide outbreak.

Here's a quick update with some developments for the lume1 project. I received boards for Aux LEDs for the FW3A flashlight and their variants. Unlike regular AUX boards, this one takes advantage of the full RGB capability of Anduril, allowing for a host of different features and capabilities.

Here's the LED board. A total of 18 LEDs for board, 6 of each R, G and B LEDs.

I had some other colour LEDs so I populated them as follows - pink as red, warm-white as green, and cyan as blue. The LED board is a little thick in this iteration, and 0.8mm PCBs should be better, but this works as well. LEDs used were 0603 LEDs on large 0402 pads. I had ordered 0402 LEDs but they haven't yet arrived.

AUX LED control is the same as the one implemented in Anduril for 1634 MCUs such as in the Emisar D4V2 and the Noctigon K1. There are several different modes such as different colours (red, green blue, yellow, cyan, magenta, white), as well as 'rainbow' and battery voltage display. There is also high and low brightness control.

Recommend LED wiring is 24-20AWG depending on what you have. For the LED wires, I used 30AWG.

After soldering on the LED wires to the AUX board above.

And finally, here's the Aux board in action, compared to a glow-gasket with my FW21. In this photo, I had previously used a green-yellow LED for the green channel. I since replaced that with warm white since I thought it came out better.

More to come soon.

Stay safe and healthy everyone!

It would be perfect, if you make variant to work with different color leds. As example, we could repower Sofirn IF25 with efficient Anduril driver. And any such flashlights in future.

Anduril has support for 3 aux LED channels, typically named R, G and B, but you can use whatever LED colour you like. Or am I missing something you're saying?

I find the choice of single colour LEDs curious. loneoceans, why did you find this solution best?

This board is getting better and better.

Great work!

Sofirn IF25 have two 2700k led and two 6500k led, so we can mix them by ramping mode. And 21700 onboard. Unfortunatly, UI is not anduril, proprietary, and driver d’t look very regulated.

So it would be nice to have high efficient Anduril driver, which can have two separate channels for two groups of different color temperature leds with ability to slide from one to another.

Subbed. :+1:

I appreciate the blue wire going to the G pin on the aux board, and the green wire going to the B pin. You rebel.

Hi loneoceans,

This is what we are waiting for... for the continued enhancement of FW3A, FW1a or even FW21. We are following the progress of your work. Thank you.

loneoceans. First of all awesome update on the project! Second, did you happen to see the PM I sent you?

I think D’AVerk is referring to variable CCT output. The IF25 is a two-channel quad that has WW and CW emitters. This would require duplication of the hardware I would imagine, and not a simple task on this size PCB. 4 layers and double sided architecture would be a requirement then I’d think. Unless there was a way to split the output via a PWM / duty cycle ratio between the two CCTs. In other words, boost circuit provides (e.g.) 3A total output. That current then flows into two linked FETs, where one is on while the other is off.

I could be way off base here, and likely am. I’d love to here your thoughts…

EDIT: :person_facepalming: I replied before realizing the thread had another page… Sorry folks

D'AVerk and JaredM, thanks for the clarification. Short answer - yes that's not a problem. I can definitely make a diver with multiple constant current regulated channels for tint mixing. I didn't know of any other common host which had a MCPCB for multi-temperature LEDs other than the BLF lantern, but the lume design is easily adapted for this purpose. It's also supported in Anduril. In fact, I reached out to the BLF lantern team if they were interested in such a design since I thought it would be ideal for both the large BLF lantern LT1, as well as the upcoming mini lantern. I got some positive feedback but no request to design one for it yet, so I guess we'll see how it goes. I would imagine that any sort of switching regulation would be ideal for a lantern, as opposed to using a linear driver, since long run-times and relatively low brightness is the typical desired scenario.

Thanks for your message, I did receive it and have replied. Thanks!

Ha yes a mistake while soldering the wires which I didn't really care about, since I was planning to swap out the green LEDs with some warm white ones later on. Nonetheless, good catch!

Agro, what do you mean the choice of single colour LEDs? Do you mean why I used single LEDs for the RGB array as opposed to using a single compact RGB LED? If that's your question, most RGB LEDs are common anode and would not fit the architecture on the board (as designed, without adding some small FETs for example, though this would remove the 'dim' mode for the AUX LEDs), and I had some other fun-colour LEDs I wanted to use such as pink and cyan, so I thought going for 18 individual LEDs would allow more flexibility. At the moment LEDs are arranged in 3 banks of 6 so you can only use 3 colors. Perhaps in a future design I can add series resistors for each, but it makes the board a little congested, as opposed to right now where it's quite symmetric and easy on the eye :).

Finally, I still have one question I'd like to ask BLF which I haven't found a solution for - anyone knows what spring Lumintop uses for the FW3A driver battery spring? I can't find one as nice as the one they have. The closest I can find is the gold plated qlite/105C 4.9x5mm springs but those are still a little too tall and don't compress as nicely as the conical FW3A spring (which also look to be silver plated?). Alternatively, any other good replacements you know of to recommend? Thanks!

I think the curiosity about the aux LEDs is because the current RGB aux Anduril flashlights like the D4v2 or FM1 can blend colors. For instance, the D4v2 can do yellow or magenta.

With single LEDs you could not do that; from many angles you would very clearly see R+G or R+B.

Yes, that’s what I meant.
But I fail to understand the answer…the first part of it :blush:
I see that your board has fields R,G,B,C which I read as Red, Green, Blue, Cathode.
So by going with separate LEDs you switch from common anode to common cathode, right?
Now…what is the reason for this switch? :slight_smile:

Very interested in this driver.

I see your point treellama and Agro... the reason for this choice was due to the lack of cheap common K RGB LEDs on non-aliexpress sources (I had ordered some previously on Aliexpress but it's been a few weeks and they haven't arrived yet), so I decided to go with individual LEDs with the benefit of more fun colours (which I already had on hand). In addition, the MCU VCC voltage is 2.5V for this board so we should not use common A LEDs, not to mention, we also want to take advantage of LED dimming in Anduril (which uses the internal 10k pullup), common cathode LEDs need to be used as opposed to common anode. Changing the design to fit RGB LEDs is very straightforward.

Is this something that people would prefer over individual LEDs? If so, I'll release both boards, one with individual LEDs and one with RGB LEDs so anyone can build their own :). They will provide a different look, which I guess is a matter of preference. In order to reduce standby current, Anduril does not PWM the AUX LEDs though, so just something to keep in mind (otherwise we can do a lot of nice effects like blendy RGB modes). Finally, a thing to note about the lowish 2.5V drive voltage - this does have some limitation if you want really bright AUX LEDs - this is just about possible with very small series resistors for the blue LED, but will affect overall look when using the 'dim mode'. This depends on the specific LED used though, and their associated V_fwd. Otherwise, it works ok.

Cheers

Really great design loneoceans.
3Amps for regulated mode is perfect in my opinion. It is usually enough to keep around 1000 lumen beam.
I saw there was already question for schematics, but I think I missed answer. Anyway I think that if you would like to see this design in more lights it could be good idea to share schematic together with component list as some of us here are able to adapt it to different pcb layouts for other flashlights.

Nice work there dude!

It would be great to bring high-efficiency drivers to a wider audience. At the moment, the more complex switching drivers are generally limited to those who can design ones themselves, or who can do the SMD soldering etc required to have a version of an existing design. (With a few exceptions e.g. buy one from Lexel)

If there could be an interest list to get a better economy of scale, it seems from community feedback that this would prove quite popular.

I think quite a significant proportion of FW3A owners would be interested, especially as that light is already an enthusiast-level design that anyone can buy.

I’m very interested in helping beta testing, I’ve sent you a PM.

Has anyone had any luck finding a spring for the driver? The closest one I found was at Kaidomain and required cutting down.