Yep, I added an edit a few hours after posting, on realizing that the voltage divider could be outside the board. I’m just hoping for enough pads to handle several sensors and/or auxiliary leds, of which the USB power detection could be one. I haven’t looked at any of the boards with USB charging and in case it isn’t clear, I’m an ok programmer but I’m not that clueful about hardware. 
Oh but it would need to be on the front I guess, I would need to squeeze the AUX pads closer together to fit another one.
I made two of the new version, one for a D4v2 and one for a KR1.
I started with the KR1 :
To have sufficient height for the 3mm inductor I used 0.8mm (0.9mm actually) boards with a spacer, as bonus they have 2oz copper weight.
Eurekatronix B35A boards have the holes at 90° so I drilled two new holes for the wires.
B35AM 4000K 9080 installed and at the lowest level (3μA) :
With the Ledil Olga RS
I haven’t yet made an AUX board for it, which is a good things because I planned to have the optic sit on the 0.9mm AUX boards, except after testing I see that raising the optic by 0.9mm degrades the beam quite a lot, a small but obvious egg yolk on the spot and the ghost LED image at the corona that JaredM talked about. I’ll have to make a big hole for the optic in the aux board.
About the driver, I configured it to 3A for the B35AM, it can take more (up to 4A) but I prefer a longer turbo.
That said I’m wondering if the thermal regulation is actually working, I haven’t tested that before because it was only on my test bench with the LED on a heatsink, the temperature reported is also low, I wonder if I messed up something in the code, when modifying the VREF maybe ?
The little flash that I mentioned at turn ON with the MP3431 is still there but greatly reduced with the hardware delay on the HDR FET, I’d say it makes a very short ~0.5mA flash now, hardly problematic.
This is starting to look pretty good ngl 
Omg
Heavy breathing….
This is still your attiny1616 board? Is there a UPDI connector? I will spend some time looking into the GDB interface for UPDI. It will be great if we can interactively debug the flashlight. Then you will be able to look at the reading from the internal temperature sensor from the debugger, for example. Meanwhile, is there already a way to blink the temperature measurement in at1634 Anduril. If you had to port it to the 1616 and aren’t sure of it, it seems straightforward to test it with a heat gun and/or some coolant spray.
Pretty good? That looks incredible. Great work
(pics removed from quote)
Yes I’m only using the t1616. There is a UDPI pad for flashing, on which I can solder a wire if I need to do more stuff. But for most of the firmware debugging I can just use my xplained nano dev board (I replaced the 416 by a 1616 on it). Yes I shoud look into the temp sensor reading via UDPI debugging.
The Anduril temp reading is weird, it does one flash, pause, then a series of flashes, pause then another series of flash. Like the temp is in the hundreds or something…
Thanks, there are still some stuff to iron out but mostly firmware now, improve the ramp, check the temp reg, and I’d like the dual sense HDR to be properly supported.
That quote though, can you edit and remove the pics?
Done, took some doing on mobile
For D4v2, do you think you can include a series resistor to limit current to the pushbutton led? The low standby mode right now uses the pullup included in the MCU, but it is still way too bright in my opinion. It should be about 10x lower, equivalent to a small tritium marker. Just bright enough to find the light in the dark.
Very nice work!!!
Well firstly it lacks a fourth aux led pad, I thought about adding one when drawing the board but decided to place well spaced not too small pads for easier wire soldering.
Secondly there isn’t much space left for aux led resistors, if I had used 0402 passives I would have had plenty but decided to use 0603 for easier building, I also don’t want to squeeze the components more, I built Mike C 17mm boost driver and I though the components where packed a little too close together, I would have find it easier to make it if it used 0402 actually.
Once there is full Anduril support I can remove 4 0603s so I’ll have a bit more space on the back for adding resistors (I’ll need to shuffle things arround so it depends how that turns out).
That said is it really necessary? the button led resistor can be changed, the retaining ring needs to be popped out but I saw people complain about it popping out on its own so it must not be very hard to remove.
I’ll see if I can use slightly smaller, closer pads to include a 4th one on top, which could serve as a miscellaneous pin as you suggested, when not used for a button led.
Thanks.
Aside from that I finished drawing a smaller one with 14mm clearance diameter :
It uses a TPS61178 which I can run at a higher switching frequency so that I can use a smaller inductance and capacitance. It will be limited to 20W (e.g. 3A at ~6.5V).
I also modified the TPS61288 version to hopefully eliminate or reduce enough the noise at low current :
Capacitor coupling and increase of capacitance as mentionned in the article about MLCC noise I linked previously.
I added a lot more vias for better thermals.
I just realised something though, the output of a boost converter is always connected to the input via the high side FET body diode, meaning any kind of resistor load on the output will always draw a current… like the resistor I added to prevent the TPS61288 switching frequency going too low, for example 10k (500 uA at 5V) resistor will have a 370~230uA parasitic drain, not great. A solution would be to wire it to a NFET and only turn it on when necessary. Which means another ramp controlled pin (I only hacked support for one (HDR FET) in Anduril).
I may have misunderstood but I thought you could only select between low and high current to the button led. The high current is controlled by a resistor on the board that can be changed, but the low current is controlled by the on-chip pullup that can’t be changed. So making the current even lower requires adding another resistor.
Or do you mean change the resistor that currently controls the high, to make it lower than the existing low? I didn’t realize that was possible, but if it is, that is good enough imho. I don’t feel that the high mode for the button led is really good for anything in the d4v2.
As a matter of preference (i.e. this is just me, others may feel differently) I find the button led great as a locator, but the aux leds for that purpose aren’t that useful. So I don’t mind giving up the ability to light the aux leds during standby. By giving that up, maybe the board can be simplified by replacing the RGB aux leds with digitally controlled ones (APA102). That might eliminate some wires, and also allow controllng the aux leds individually from software.
Wouldn’t the body diode of a pfet be in a blocking configuration?
s. nice work on the boards, design, artwork, assembly and soldering, etc. you have moved up to the top tier in my book. Very clean layout and not crammed in. This is the difference of someone who knows and understand flashlights and modding versus someone just cranking out boards for sale with no understanding…
I agree thefreeman, you’re an inspiration to the community with your persistence and attention to detail.
I’m jealous of the KR1/B35/Olga/driver setup.
Have you tested the spectrum of these B35s? What’s the Duv and Rg if so?
EDIT: Also curious what kind of intensity you are seeing from the setup. About 20kcd is my estimate… close?
Thanks, I have learned a lot of things in the process.
There is one thing I will change that is increasing the 0603 footprints lenght, current ones are a little short and I think this is going to be less reliable (shock resistance).
Edit : forgot the question… most high power boost converters use high side NFETs (with a bootstrap capacitor to get the required VGS). Check the diagram Page 16
But regardless, I don’t think it would works if the PFET or NFET was reversed, there would be a reverse current going through its body diode and the low side FET when the later is ON.
Here is a TM-30 report of 3500K No1 with an Olga RS :
Tint shift vs current :
Duv binning at 5mA :
The 4000K is the one in the KR1, unfortunately the AR coated lens adds +0.0015, (bad) AR coating is a blight for us tint snobs.
I’ll come back with an intensity measurement (need to check if the sitting height of the optic affects it)
This reminds me. We need to get on hank to start using a green reflecting AR coating. Going to comment in that thread. Hopefully others pile on and he gets the idea how important this is to so many of us.
And that 3500K report looks stellar! 102 and –0.0030 are just about perfect IMO. R9 of 84 isn’t bad either.
I don’t think he replied to messages me and Lux-Perpetua made about it unfortunately, but more support should help.
R9 is 84 but it’s slightly oversaturated (1% chroma shift on hue bin 1) anyway so it’s better than 100 IMO.
This shows the limitations of CRI, we can see it on the CIElab plot but not in the CRI numbers :
Hank can be quite stubborn. Hopefully his recent engagement with BLF is continued, but I’m not holding my breath. I left a comment just now…
As for the limitations of R9 and CRI, I am on the same page. The values I care about most are Rg and Duv. Very close second is Rf(skin). R9 is a ballpark figure, and about 75 is good in my book… Beyond that, I have to see the details like you point out here. Hue shift to a certain degree doesn’t bother me and quite frankly is tough to pin down what is “accurate” in real life, since there is no light source that is “perfect” and consistent to compare against. Even sunlight, by the time it’s filtered, reflected, and refracted through windows and of walls and furniture is not really much of a ideal reference anymore. Chroma however is very noticeable and I prefer a 2-3% oversaturation - and preferably most in the reds and blues, with neutral greens. This emitter is knocking most of this out of the park! I do prefer about 500-1000K cooler though for an EDC, but this seems like a splendid option for the more relaxed evenings and outdoor recreation.
That’s what I mean yes. That said I tried removing the retaining ring but haven’t had any success yet…
Post 163 - so this is what it looks like when enthusiasts flashlight history is being made.. nice! I must be feeling kind of what everyone was feeling a few years back when lexel was doing his thing too?
this is AWESOME. I cannot contribute anything but that. Thank you Freeman!