[[ GXB20 Driver – Homemade Constant Current Programmable XHP50 Single-Cell Boost Driver! ]]

204 posts / 0 new
Last post
M4D M4X
M4D M4X's picture
Offline
Last seen: 2 months 3 days ago
Joined: 03/19/2014 - 05:17
Posts: 8821
Location: Austria (GMT + 1)

welcome to BLF!

you found the right spot for your great project!


PLEASE NOTE
i do not work in "reviews, deals and codes" for the time being
maybe M4D M4X will return one day, but until then:

THANK YOU FOR YEARS OF YOUR SUPPORT AND FRIENDLY CONTACTS!

DavidEF
DavidEF's picture
Offline
Last seen: 2 weeks 6 days ago
Joined: 06/05/2014 - 06:00
Posts: 7699
Location: Salisbury, North Carolina, USA

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. Silly

The Cycle of Goodness: “No one prospers without rendering benefit to others”
- The YKK Philosophy

Serp
Serp's picture
Offline
Last seen: 8 months 2 days ago
Joined: 01/14/2014 - 11:29
Posts: 626
Location: Ukraine

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
http://forum.fonarevka.ru/attachment.php?attachmentid=135950&d=1429901214

P.S. My Indigo (20mm Rocher F6) http://forum.fonarevka.ru/showpost.php?p=868616&postcount=360
15W its ultimate load

P.P.S. http://schmidt-walter-schaltnetzteile.de/smps_e/aww_smps_e.html

P.P.P.S Another driver http://forum.fonarevka.ru/showthread.php?t=26562
When using an external amplifier brightness does not change when the battery discharge. And there is a free one leg of the microcontroller.
http://forum.fonarevka.ru/showpost.php?p=959082&postcount=223

kiriba-ru
kiriba-ru's picture
Offline
Last seen: 1 day 13 hours ago
Joined: 01/17/2016 - 02:34
Posts: 2128
Location: Russia

1uH vs 3.3uH is big difference.

Khuan
Khuan's picture
Offline
Last seen: 8 months 2 days ago
Joined: 06/10/2016 - 13:09
Posts: 63

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!

FlashPilot
FlashPilot's picture
Offline
Last seen: 6 hours 2 min ago
Joined: 05/10/2010 - 16:07
Posts: 4812
Location: USA

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? Big Smile

Id love to hear about some of your other projects when you have time to post.

erik
erik's picture
Offline
Last seen: 3 months 1 day ago
Joined: 04/10/2015 - 05:00
Posts: 157
Location: italy

wonderful, thank you

AEDe
AEDe's picture
Offline
Last seen: 11 hours 13 min ago
Joined: 12/01/2016 - 12:07
Posts: 716
Location: Moscow

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.

TheOnlyDocc
TheOnlyDocc's picture
Offline
Last seen: 11 months 2 weeks ago
Joined: 06/26/2015 - 05:17
Posts: 949
Location: Mönchengladbach /Germany

Ramping is something i absolutly like in a flashlight Firmware. Like the Narsil FW (http://budgetlightforum.com/comment/922763#comment-922763).

New WildTrail (former LuckySun) D80v2 Sale has Started http://budgetlightforum.com/node/66255

tuelleric
Offline
Last seen: 7 months 3 weeks ago
Joined: 12/05/2016 - 12:17
Posts: 110
Location: Germany

Hi Loneoceans,

This is indeed a very impressive first thread! It addresses exactly what I am currently looking for.

I want to put a Nichia 144AM from the BLF group buy in a single cell light. The only driver I have found so far that is at least capable to deliver 2.5 A is the FX35 from Kaidomain.

However, I absolutely do not like the 5 modes with strobe and so on. Short question here: Is it possible to change the firmware on that one?

I am really looking forward to seeing the GBX20 or GBX17 become a series product! I’d be in for a couple of these!

T18
Offline
Last seen: 2 years 2 months ago
Joined: 02/14/2016 - 15:29
Posts: 1163

Welcome Loneoceans you’ve sure have made a great first impressions, absolutely amazing, a weekend project?
Wow, wondering what your capable of in a week?

Majoroverkill
Majoroverkill's picture
Offline
Last seen: 5 hours 40 min ago
Joined: 01/12/2017 - 17:13
Posts: 1011
Location: Nevada

I would definitely be interested in a few. Just getting into modding flashlights and love it! Big Smile Just bought a SMD 862D+ rework soldering station today.

Doug S.

tuelleric
Offline
Last seen: 7 months 3 weeks ago
Joined: 12/05/2016 - 12:17
Posts: 110
Location: Germany
Majoroverkill wrote:
I would definitely be interested in a few. Just getting into modding flashlights and love it! Big Smile Just bought a SMD 862D+ rework soldering station today.

My Atten 858D+ is on the way, too Smile

Majoroverkill
Majoroverkill's picture
Offline
Last seen: 5 hours 40 min ago
Joined: 01/12/2017 - 17:13
Posts: 1011
Location: Nevada

Sweet! I love new toys that make fabricating easier Big Smile

Doug S.

loneoceans
loneoceans's picture
Offline
Last seen: 6 months 1 week ago
Joined: 01/08/2017 - 00:18
Posts: 283

Hello all,

Again many thanks for all the kind words! I've been pretty busy lately but I managed to do some comprehensive testing across 20 power level settings which folks might be interested.

Before that, I want to say that I really appreciate all the comments and feedback I've received. But I'd like to reiterate that I never designed this project with an intention to sell them and make a profit, nor to produce a 'commercial' product - this was just a project I did just for fun and I did not plan to develop this extremely comprehensively and be fully featured, as I would have if I had designed this as such. As a result, I understand this driver has many flaws and 'lack of features', but I hope you can understand the motivations of the project! Smile Some of you have pointed out some of the nice Russian drivers - they look great and a lot of respect to the folks who have made it as well! I'm not making this as a competitor, just making this driver as a fun project. And if people like it and would like to use the driver (with its particularities and feature (or lack of) set), or to continue to develop it, I'm more than happy to help!  smile 

That said, given the big interest, I'll try to work a bit more on this driver and see if I can create a nice 17mm version when time allows. The use of a fairly powerful MCU also opens a lot of possibilities like soft-buttons and other features. I also made a whole bunch of PCBs (since making a batch is the same cost as making 1!), I'd be offering some for sale soon once I make sure the driver is actually worth putting into a flashlight tongue-out, so do let me know if you're interested. As a side note - what's the typical implementation of a soft button on flashlights and what should I design it for? E.g. are there any popular hosts I can take a look at that you can recommend?

Ok so back to the test!

The test was conducted as follows. The driver was hooked up to a constant voltage programmable Agilent power supply. In this case I conducted the test at 3.7V in across the range (driver was also tested at a variety of input voltage from 4.5V to <3V but less comprehensively). Input current and voltage was measured via Kelvin terminals to avoid errors due to lead resistances. Output current was measured across the load resistor as well as the output to find total driver efficiency.


A total of 20 constant current levels were tested and measurements taken. 

 

Above shows a photo of the test in action. The XHP50 LED was mounted on a 20mm star heatsink, which was in turn mounted on a big heatsink to keep it cool during tests. As a side result, the data will likely be inaccurate as the LED die temp rises, but I really don't have so much time to do a full datasheet-style test yell

 

Here's an example scope shot showing the driver output at 5 different power levels. This was achieved by configuring the on-board MCU to run a 'test program' during startup at different power levels for 1 second each. Cyan shows output voltage and yellow shows voltage across the current sense resistor. Regulation is fairly clean, as expected with the very high switching frequency. 

 

In this test, the maximum power tested was a massive 22.4W into the driver, driving the XHP50 LED at a measured 3053mA. At this power level, just putting my finger near the LED light feels very hot! Based on the specific bin of XHP50 I had on hand, this translates to a datasheet lumen output of around ~1700 lumens. Lower CRI bins less than this 90+CRI one used should yield close to 2000 lumens. As mentioned, heatsinking becomes very critical at these levels. 

Maximum efficiency was measured at around 98+% efficiency at lowers loads of around 750mA out.This drops gradually to 87% or so at 3A output, meaning about 2W dissipated in the driver itself! Most of the heatsinking of the driver occurs through the ground ring around the driver so mounting it in a host properly is also critical. Increased temperature after longer runs will certainly affect the efficiency though. In all the driver seemed to regulate current just fine all the way up to the maximum 3A load.  Finally, keep in mind that this efficiency number should probably be treated more as a guideline. I expect the efficiency to actually be better since there probably is non-trivial ohmic losses in connection points / spring, and a properly seated driver in a good host with a good switch should do a little better. So this efficiency is the measured system efficiency, driver efficiency should be a little higher (esp on the high currents). Finally the shape looks roughly in-line with my simulations should it at least gives me a good confidence in my measurements. Overall approaching 90% system efficiency is still pretty good for me!

In reality, I will likely turn operating current down to closer to 1.8A for a total lumen output of just around 1000 lumens of 90CRI light! This is due to the relatively poor heatsinking design of the host. Perhaps one day I'll mod this into a 'real' flashlight! 

Overall I'm quite happy with the results as they are around the ballpark of what I expected, and most of all, I'm very glad that I didn't mess up the PCB (which is pretty rare given that this is my first run!). The next step is to work on the firmware for modes, and finish a more detailed write-up on the driver. I'll also be finally putting this LED driver into a host and do some beam comparison shots with the stock 'LatticeBright' LED and its driver, with this new driver!

More to come soon and thanks for reading.

www.loneoceans.com/labs/

- Next-gen Switching Drivers: Lume X1 and Lume1
- High Power Boost Drivers: GXB100 GAN 100W, GXB172 17mm 50W
- Older: GXF22, GFS16, GXB17 & GXB20

MRsDNF
MRsDNF's picture
Offline
Last seen: 2 months 1 week ago
Joined: 12/22/2011 - 21:18
Posts: 13473
Location: A light beam away from the missus in the land of Aus.

Amazing work loneoceans and love the testing. Thumbs Up

 

djozz quotes, "it came with chinese lettering that is chinese to me".

                      "My man mousehole needs one too"

old4570 said "I'm not an expert , so don't suffer from any such technical restrictions".

Old-Lumens. Highly admired and cherished member of Budget Light Forum. 11.5.2011 - 20.12.16. RIP.

 

Rufusbduck
Rufusbduck's picture
Offline
Last seen: 6 months 5 days ago
Joined: 04/04/2012 - 15:34
Posts: 10389
Location: Golden state
Beer Wow, you’ve really hit a home run here. I’m pretty sure you can find a company to further the developement and bring it to market. You might hook up with a local member or three for testing and feedback but it would be worth your while to connect with some of the more avid and skilled driver gurus to gain insight into the pulse here. Aside from the dimple in the bottom the main difference between sinkpad and Noctogon is trace width(Noctogon having much wider traces) and hex vs round. There are some lights that take 20 mm drivers but more common is the 17mm size which is a big hit in acreage. Until recently almost all the DIY programming was done with the Attiny 13A but in the last year or so the trend has been towards the 25/45/85 or the much smaller mmu mcu’s where space is at a premium(10-15 mm drivers). Rich(RMM) at Mtnelectronics or Illumn might be a good sales partner in the US or 3tronics in the UK and cutter electronics in Australia. Simon at Convoy might be interested as well. Most of us struggle to understand any more than the basics regarding boost and buck drivers so your enthusiastic reception is no surprise. Fair warning: there will be questions headed your way. Wink

Three Tanna leaves to give him life, nine to give him movement. But what if he eats the whole bag?

Scott

AEDe
AEDe's picture
Offline
Last seen: 11 hours 13 min ago
Joined: 12/01/2016 - 12:07
Posts: 716
Location: Moscow

Thank you for the tests!

loneoceans wrote:
As a side note – what’s the typical implementation of a soft button on flashlights and what should I design it for? E.g. are there any popular hosts I can take a look at that you can recommend?

There are many flashlights with soft button.Typical size of driver is from 18.5mm to 21mm.One of popular hosts is skilhunt H03
Its a bit hard to disassemble because it is sealed with thread. Or H02 it have very convenient construction for modification.
tjeret
Offline
Last seen: 4 years 3 months ago
Joined: 11/18/2014 - 07:12
Posts: 107
Location: Indonesia

Those efficiency number is impressive
Thank you for your test and a great tools you have there Smile

loneoceans
loneoceans's picture
Offline
Last seen: 6 months 1 week ago
Joined: 01/08/2017 - 00:18
Posts: 283

Some updates for the week!

 

To summarize, I finally finished a 'beta' version of the firmware, put it inside the host, and now have a single 18650 XHP50 flashlight producing 1700+ lumens of 4000K CRI90 light!

 

Firmware Work

I spent about an hour or so yesterday and tidied up the basic functionality of the firmware (currently v0.6). It has all the basic functionality - 4 modes at 60mA, 540mA, 1800mA and 3000mA. Using the G2-bin LED I'm using, this corresponds to around 35 lumens, 310 lumens, 1000 lumens and 1750 lumens from the emitter. Keep in mind that if the most efficient bin was used (J4), a whopping 2500 lumens is possible!

The brightness levels chosen was somewhat arbitrary with no specific reason. Mode change goes from level 1 -> 2 -> 3 -> Brightest, with memory mode tested and working. Low battery cut-off was also tested and working. Thermal cut-off was difficult to test, but I did at least verify that it was reading the right temperatures. Clearly more robust testing is required later, but for my own 'demo' torch, this should do. 

Obviously a lot more testing is required before I would consider a firmware stable, hence it's now labeled as v0.6 instead of 1.0 tongue-out

 

Assembly

With the beta firmware done, I loaded it up to the LED driver, then removed the programming header and prepared it for mounting.

As recommended, I also did a spring bypass with teflon coated stranded wire. Above shows the logic/driver side.

And here's a photo of the 'power' side with all the power electronic components.

As some of you may remember, I was doing testing with a G2-bin XHP50 LED with 90CRI and 5700K temperature. I wanted something a little warmer so I opted for a 90CRI G2-bin 4000K XHP50 instead. This time I had some proper heatsinks (from the recommendation of many members here), so I reflowed the 4000K LED onto it - this will go into my flashlight.

This was then fitted into the housing and thermal paste applied between the LED-sinkpad and the housing.

The wires were trimmed and soldered down.

And finally it was assembled into the host! It looks just like the original... but actually contains a light monster!

Above you can see it sitting beside the older XHP50 (5700k) mounted on heatsink, which I used for testing.

The project is done!

 

Comparison Shots

So how does it compare? Let's take a look at some beam shots. In order to compare, I set my camera to have a fixed manual exposure of 1/60s, ISO 400, W/B 4500K, f3.2. I compared the new XHP50 flashlight with the following:

1) 3000K 800 lumen Greenlite LED bulb (8.4W measured)
2) 5000K 1700 lumen CREE LED bulb (2016 version) (15W)
3) SK68-3W - cheap AA LED flashlight - 1.28V at 2.00A via Eneloop HR-3UTG (2.56W measured)
4) SK98 stock with LatticeBright 6500k+? (6.74W measured)
5) SK98 replaced with Cree XML2 80CRI 3000K (6.67W measured)
6) SK98 with GXB20 with Cree XHP50 90CRI 4000K (22W measured)

All 18650 batteries used in the SK98 Ultrafire host were the venerable LGDBHE21865 high discharge cells.

The above photo shows the unedited images with (1) on the top left and (6) at the bottom right. The result speaks for itself I think! It's extremely bright! Also, I specifically under-exposed as much as I could to (a) retain luminosity data and not blow highlights and (b) since I expect myself to make more, brighter lights in the future! surprised

 

And finally, with the lenses zoomed all the way in to give an idea of the 'throw':

From left to right: 

  1. LED AA flashlight (no idea what's inside)
  2. Lattice-bright XML-copy LED in SK98
  3. Cree XML2 in SK98
  4. Cree XHP50.1 in SK98

I think it's pretty clear that the Lattice Bright LED does have a smaller die and different phosphor coating than the XML2, and again from the XHP50 which has 4-dies. Hopefully the XHP50.2 will improve the cross pattern. Regardless, I think it's a pretty interesting pattern (which only really becomes annoying at max zoom), so I don't really mind it at all given how much light it provides! 

 

So overall I think this project is a success! Thanks again for reading and following my little project! 

Next step is to refine the firmware, do additional testing and see how it does in the real world, and then perhaps start on the GXB17...

 

[Edit] - Did a little bit of real world testing of the firmware and it appears that thermal management is working as intended Smile

www.loneoceans.com/labs/

- Next-gen Switching Drivers: Lume X1 and Lume1
- High Power Boost Drivers: GXB100 GAN 100W, GXB172 17mm 50W
- Older: GXF22, GFS16, GXB17 & GXB20

T18
Offline
Last seen: 2 years 2 months ago
Joined: 02/14/2016 - 15:29
Posts: 1163

I am very impressed and if you should decide to brings these to market I’d certainly be interested in at least 4-5 of these drivers.
Just start a thread or continuance here maybe and post a notice and I’ll be there, thanks for sharing your project it’s fantastic.
Edit: Maybe an interest list would give you an idea of what might be possible and needed for your parts etc.

Majoroverkill
Majoroverkill's picture
Offline
Last seen: 5 hours 40 min ago
Joined: 01/12/2017 - 17:13
Posts: 1011
Location: Nevada

Wow, very nice!

Doug S.

texas shooter
Offline
Last seen: 31 min 48 sec ago
Joined: 08/26/2012 - 02:14
Posts: 1765
Location: Texas

Very impressive and very well spaced modes. Congratulations!!

gchart
gchart's picture
Offline
Last seen: 14 hours 42 min ago
Joined: 03/19/2016 - 11:57
Posts: 3158
Location: Central IL

I love it when a plan comes together

Well done, loneoceans! It’s great to see some real-world test results. Now only to… (1) find a way to make a 17mm version, and (2) find a manufacturer to produce them on your behalf, to your exact specs Smile

Lexel
Lexel's picture
Offline
Last seen: 11 months 2 weeks ago
Joined: 11/01/2016 - 08:00
Posts: 5895
Location: Germany

Why not create an Oshpark project?

MRsDNF
MRsDNF's picture
Offline
Last seen: 2 months 1 week ago
Joined: 12/22/2011 - 21:18
Posts: 13473
Location: A light beam away from the missus in the land of Aus.
Smile Thumbs Up

 

djozz quotes, "it came with chinese lettering that is chinese to me".

                      "My man mousehole needs one too"

old4570 said "I'm not an expert , so don't suffer from any such technical restrictions".

Old-Lumens. Highly admired and cherished member of Budget Light Forum. 11.5.2011 - 20.12.16. RIP.

 

The_Driver
The_Driver's picture
Offline
Last seen: 2 months 3 days ago
Joined: 10/20/2016 - 05:51
Posts: 1462
Location: Germany

Very nice!
How about an additional moonlight mode? How low can this driver go (without flickering)?

Firelight2
Firelight2's picture
Offline
Last seen: 4 hours 1 min ago
Joined: 04/08/2011 - 15:17
Posts: 4632
Location: California

Awesome job!!

I want one! Maybe more than one depending on price. Cool

RobertB
RobertB's picture
Offline
Last seen: 1 day 33 min ago
Joined: 12/18/2015 - 17:49
Posts: 3727
Location: USA, Michigan

Sounds like this is what I need for the Nichia 144A’s I bought from Clemence/TA being able to use a single cell. Nice job loneoceans

MRsDNF
MRsDNF's picture
Offline
Last seen: 2 months 1 week ago
Joined: 12/22/2011 - 21:18
Posts: 13473
Location: A light beam away from the missus in the land of Aus.

From wo to go you have amazed. What an effort. Beer

 

djozz quotes, "it came with chinese lettering that is chinese to me".

                      "My man mousehole needs one too"

old4570 said "I'm not an expert , so don't suffer from any such technical restrictions".

Old-Lumens. Highly admired and cherished member of Budget Light Forum. 11.5.2011 - 20.12.16. RIP.

 

Pages