^ about 12V, i think he(we) can modify the Feedback Resistor, so the voltage can change
if only this driver is 17mm
Btw , the led you use is a LatticeBright (not original Cree xhp50) , i hope you know 
Well i don’t know , i only commented the led on the photo 
no, he reflow the XHP50 on the old MCPCB
Especially with 18W on a 5050 package you need a DTP star
Also a spring bypass should improve the lights performance as you get less voltage drop and heat
Oh yeah, thanks Lexel! I forgot to mention the spring. I knew there was something else! The spring needs to be upgraded at least! Or, as Lexel says, a “spring bypass” can be done. Look that one up. There are a few ways to do that, and it’s definitely a big improvement for high wattage lights!
I’m certainly interested in the schematics. Are you going to release them too?
@ loneoceans,
Welcome to BLF.
You certainly know how to make a Good 1st Impression.
Most of this stuff is beyond me, but good to see someone addressing the needs of the Members.
I’ll be interested to see how this all pans out.
Cheers,
Splott-Light
P.S. If you get your “Milla” off Raccoon City, you’’re then “Officially” in!
As a first post and “weekend project” Saying Welcome to BLF and thanks for your contributions so far is not enough.
Thank you and welcome to BLF.
Lot of information through these pages. And we’ll mug you with it all. So just ask when needing component sources or already researched material.
Thanks for the warm welcome DavidEF and everyone here :). Thanks for the heads up for DTP heatsinks!
I reflowed the old XML LED off the original heatsink and replaced it with a XHP50 but as I've found, it gets very hot very quickly. As a result I've in fact ordered a few 20mm copper 'Sinkpads' for additional testing. I did some reading up and it appears that Noctigon is another good brand? These should perform better and I plan to do a quick thermal comparison test to try to quantify the improvements. Would appreciate additional suggestions for good heatsinks (short of just making my own! Though I'd like to keep to the spirit of this project which was to do a simple modification of an existing low-cost flashlight).
For reflow - I do reflow in an over on a regular basis, but I didn't send stencils to be made for this project just yet! I suppose if this project is successful enough I'd make a stencil so I can do a small run perhaps ^_^.
Again thanks on the input for 17mm, I'll definitely be trying to see how I can optimize the design for 17mm. One thing I'm concerned about is the drivers thermal performance and I tried to take as much care as possible during layout to ensure that the power components have good thermal sinking to the ground planes (and eventually to the outside ring to the host). For larger driver sizes I think it makes more sense to optimize it for even better components for less loss and to add some nice to have features such as larger packages for easier soldering and programming. But I'll like to focus on the GXB20 first, then perhaps 'GXB17' :)
Finally, with very minimal work (or in fact... none at all!), this driver can certainly drive 12V LEDs! This is a constant current driver so it will easily generate 12V to match the desired load current. I'll have to re-check the components (e.g. the output capacitor needs to be replaced with a higher voltage one, safety protection features need to be adjusted etc) but making it a 12V driver will certainly work. The reason I went for 6V was due to the fact that (1) commonly found XML heat-sinks have footprints compatible with XHP50 in 6V configuration and (2) I did some quick simulations on the boost drive and it's a little bit more efficient at 6V output compared to 12V output (across the range).
Will do - I'll try out with some Sinkpad IIs I purchased earlier (http://www.sinkpad.com/datasheet-sinkpad-2.php(link is external)) though it also seems like Noctigon is great too! I'll also document the spring bypass and additional methods I can do to improve efficiency. Speaking of springs, does anyone have any recommendation for good springs I can use which are not too large? For example the one I'm using now has a fairly large 8.5mm base spring which limits PCB space. I was looking at some springs like the 5mm or 7mm base springs on (http://www.mtnelectronics.com/index.php?route=product/category&path=25_81) - are these good or do you know of better ones?
Finally, I've been reading a little bit more about the different modes in flashlights and it made me wonder - would a 'moonlight mode' be something useful? And if so, what the typical brightness that people like?
Thanks again to everyone for the encouragement and kind words and for following this project. I do appreciate your time 
I like the small Convoy driver spring on my C8 or other drivers
Its around 4mm in diameter
The tail spring does the most of the job being higher snd softer
If you got problems with heat on a 17mm driver you can put the MCU and other non power parts on a slave board similar to this
welcome to BLF!
you found the right spot for your great project!
Moonlight is definitely a useful mode. There are disagreements about how low it should be, however. I find that around 1 - 3 lumens works fine for me. More than a few lumens can get into being too bright for moonlight mode use. Some want <1 lumen, which is IMHO more of a firefly mode and not useful to those of us who don’t have ToyKeeper’s super night vision.
You have the ability to assemble Indigo 5
http://forum.fonarevka.ru/showthread.php?t=20409
It is an advanced driver. Like a meteor M43 but an earlier version.
power part and signal lines should be possible to remove from each other
P.S. My Indigo (20mm Rocher F6) Показать сообщение отдельно - Indigo 5.0, или "не совсем форумный" драйвер? (Часть 2)
15W its ultimate load
P.P.S. Boost Converter
P.P.P.S Another driver Драйвер для питание XHP50 и MT-G2 от одного лития. | Мастерская: Tamagotchi и Rime
When using an external amplifier brightness does not change when the battery discharge. And there is a free one leg of the microcontroller.
Показать сообщение отдельно - Драйвер для питание XHP50 и MT-G2 от одного лития.
1uH vs 3.3uH is big difference.
Hi Loneoceans, welcome to BLF!
Saw your crazy tesla coil setup in the science center but too bad it was not switch on that day…
Anyway, really hope you can make a 17mm version!
Welcome to the forum and thank you for sharing your experiences! Congrats on your successful full power test (6V@3A). I didnt think those power levels possible from a 20mm boost driver, much less your thoughts for a 17mm. Your skills are simply amazing and accomplished at blinding speeds far beyond anyone else Ive seen to date. Is this just a hobby or are you also a NASA EE? 
Id love to hear about some of your other projects when you have time to post.
wonderful, thank you
Loneoceans, there is a similar project in Russian forum , but with low current button.
http://forum.fonarevka.ru/showthread.php?t=31892
http://forum.fonarevka.ru/showthread.php?t=31484&page=3
Low current button has several advantages for example the function of beacon ,gradual increase /decrease of brightness and so on can be realised
As I know there is no such drivers on BLF.
Ramping is something i absolutly like in a flashlight Firmware. Like the Narsil FW (Q8, PMS SEND TO THOSE WITH ISSUES BLF soda can light - #2 by The_Miller).