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Flashlights => Flashlight Drivers Discussion => Topic started by: Cereal_Killer on August 10, 2014, 08:02:30 AM

Title: Lets build a 1.2-5.5v driver that takes a 13A
Post by: Cereal_Killer on August 10, 2014, 08:02:30 AM
I really want to design a boost driver for single AA (but hopefully all the way up to 5.5v for 2-4s AA or 1*Li-ion) that has one of the uC's we can all flash and have FW for (I'll also make a PIC version for those of us doing both but mainly would make an AVR one, most likely the 13A so a 105c can be stripped).

I've found a boost driver component that is highly recommended by Everett (tterev3), I believe we could easily make a simple little circuit with only a couple components to get it operating but not very efficently at the low or high end, what can we do to get it to run better at 1.2 and 4.2v, not just ~3v? Everett also suggested a SEPIC converter which I dont really understand. I do know a SEPIC requires a second inducer so its very board real estate consuming.

So its late and my brain isnt working but I wanted to get this idea out there, here is the datasheet for the Ti LM3410.  (http://www.ti.com/lit/ds/symlink/lm3410.pdf)

Ideas, comments, slightly related input, existing projects any of you guys have in the works, anything?
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: Cereal_Killer on August 10, 2014, 08:24:27 AM
I was hoping to use the smaller and slightly cheaper SOT-23-5 (5-pin version) but its looking like in order to make a SEPIC it'll have to be the LM3410XSD which is a 6WDFN package (6-pin wide, dual flat no-leads) so thats going to make it even more tightly packed ;D

yes thats supposed to be a happy face, board layout is my favorite part!


Edit: what's it take to design a driver-
(http://i452.photobucket.com/albums/qq247/1badv8dime/Killer%20Lumens/87AEBB3B-5B45-457A-8F76-B5D107B24AE4.jpg)
Computer w/ 3 datasheet's open simultaneously
2 notebooks (graph paper of course), the one on front of me is a composition book used only for the circuit design and related info / notes directly about the circuit or component.  I was taught this by my uncle who's an EE (and is now retired from a professor position at BGSU which he took after retiring from his EE career). That way years from now when I actually know what I'm doing I can look back and see how retarded I used to be. (Ok maybe not his exact reasoning lol but he is the one that taught me this method). The other spiral notebook is for more general notes / doodles / (ir)relevant info.
3 colors on pins and a lead duce. You always gotta draw your diagrams in pencil so you can erase the mandatory 800+ mistakes but to make them easier to read I go back and trace power points (+ and -) in red and black, use the black to write, the green to make comments (just like in programming) and red for extra important notes/comments.
Oh and note cards, I'm not an organized person but I am very methodical, I don't want my notebooks full of unreadable crap that make zero sense so when I originally come up with an idea or anything I need to write down I do so on the note card / post it / notepad on my phone. Later once I collect the thought / organize it into something that makes sense I put it in the appropriate notebook.
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: MRsDNF on August 10, 2014, 10:29:03 AM
I'd love to help CK but electronics and I dont speak the same language.
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: Cereal_Killer on August 18, 2014, 05:24:39 PM
Well guys not much progress on this front, I've been so busy with my other more pressing driver projects however I do have 5 of these coming.  (http://www.dx.com/en/p/3w-5w-20-mode-regulated-circuit-board-for-flashlights-7880#.U_InnqOqnDc) Now obviously these arnt the answer to this wide input voltage driver project (they wont take a li-ion) but I want to have a solution for 1AA now and designing a whole new board is not easy. Also using this already existing driver and just making a new board cut's down the work load on my end, if I have to end up doing the entire SEPIC project on my own I'll probably want to be able to sell those drivers to make it worth my time, using this I wont mind giving the stuff out open source so people can share since the basic design is already done.

If nothing else I can atleast make a 15mm board for the parts off these things and have SOMETHING to use for small 1AA lights in the mean time. Hopefully they run on PWM so I can put a 13A / PIC MCU on them (I've pretty much went to all PIC for my personal stuff but I still use AVR for everyone elses needs since y'all are behind the times lol).

Now to find a smaller toroidal inducer to fit in small lights.
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: 18sixfifty on August 18, 2014, 08:59:07 PM
Very cool stuff but way over my head. I know what most of the stuff does and how to get more out of what is there. I don't have a clue how to design.

I do know I would love a good boost driver for smaller lights. I think a whole lot of people would.

Good luck and keep us posted.
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: WarHawk-AVG on August 19, 2014, 04:57:30 AM
Got the basic schematic up

Are you wanting to driver series led's

* Input Voltage Range of 2.7V to 5.5V
* Output Voltage Range of 3V to 24V

While Googling, stumbled across this
http://laserpointerforums.com/f67/free-diy-open-source-boost-driver-tested-working-71433.html

Biggest issue I see...the daggum coil takes up ALOT of space...wouldn't be hardly any room left on a 17mm for a 13A...maybe one of those teeny PIC's

Maybe not...thing is stupid small!
(http://laserpointerforums.com/attachments/f67/36484d1328854359-free-diy-open-source-boost-driver-tested-working-1.jpg)

Seems the purple board goodness is going strong :D


Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: WarHawk-AVG on August 19, 2014, 05:16:29 AM
Damn..those 20 mode drivers look SWEET!

You gonna sacrifice one to take a peek at it :)

Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: WarHawk-AVG on August 19, 2014, 05:55:33 AM
Sepic feedback schematic?

(http://www.dz3w.com/uploadfile/2010/0428/20100428111031296.jpg)
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: WarHawk-AVG on August 19, 2014, 06:02:57 AM
Dang..those lazer dudes have some really good boost designs already made up...the biggest issue...we have to figure out a way to put PWM on them so we can have modes in our lights

I am wondering if a IRLM2502 between the LED's and the driver wouldn't be able to do that...pretty much the boost circuit does it's thing...the FET then controls the power going to the LED, in which PWM can then be controlled independent of the boost circuitry...
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: WarHawk-AVG on August 19, 2014, 06:11:47 AM
more "research"

http://rntmns.com/2012/06/lm3410-led-driver-test-board/
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: WarHawk-AVG on August 19, 2014, 06:39:20 AM
Darn thought I found a good boost candidate...then saw the 500mA max current...fooey

http://www.ti.com/product/tps61029-q1

Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: Cereal_Killer on August 19, 2014, 04:02:25 PM
I am wondering if a IRLM2502 between the LED's and the driver wouldn't be able to do that...pretty much the boost circuit does it's thing...the FET then controls the power going to the LED, in which PWM can then be controlled independent of the boost circuitry...
So your saying put the boost converter's output pin to the FET's Source leg then the LED- to FET Drain and PWM the FET? Would the FB pin (sense resistor) go before or after the FET (probably have to go before)?

The TI boost chip can be PWM'd in either mode- as normal boost circuit or a SEPIC, not sure what the laser guys are doing and if that could be PWM'd. I'm sure I could fit a 10f322 / attiny10 on there tho. One of the things I really like about PIC is the internal reference, no need for a vdivider circuit taking up space for batt monitoring.

Anyone a member on LPF and want to invite whoever designed the x-drive driver over here?
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: JohnnyMac on August 19, 2014, 05:57:39 PM
I really wish I had a clue what I was doing with this stuff so I could help out even a little bit.  I love following what you guys are up to though!  Keep up the awesome work!!
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: WarHawk-AVG on August 20, 2014, 10:08:08 AM
I am wondering if a IRLM2502 between the LED's and the driver wouldn't be able to do that...pretty much the boost circuit does it's thing...the FET then controls the power going to the LED, in which PWM can then be controlled independent of the boost circuitry...
So your saying put the boost converter's output pin to the FET's Source leg then the LED- to FET Drain and PWM the FET? Would the FB pin (sense resistor) go before or after the FET (probably have to go before)?

The TI boost chip can be PWM'd in either mode- as normal boost circuit or a SEPIC, not sure what the laser guys are doing and if that could be PWM'd. I'm sure I could fit a 10f322 / attiny10 on there tho. One of the things I really like about PIC is the internal reference, no need for a vdivider circuit taking up space for batt monitoring.

Anyone a member on LPF and want to invite whoever designed the x-drive driver over here?
Yes pretty much the FET is the on/off switch for the output of the booster, this way it eliminates all of the goofy problems with trying to make the booster do the dimming, booster runs wide open, the light switch is the FET, now PWM that from the ATTiny or your smaller PICS and VOILA

yeah it seems the PIC is a much better candidate...unfortunately not many are up to speed or have the programmers

I say we try a ATtiny 24 ;)

Plus it can be "dual purpose" for those that want a single mode, click on. just populate the boost stuff, for those that want modes, go for the gusto and add the MCU and PWM controlling hardware
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: Cereal_Killer on August 20, 2014, 02:40:52 PM
I like the idea of having it run full power without a MCU, probably need a jumper to the FET's gate or something.

What we could do it have 2 LED- pad's, one from the FET's drain and one from the boster's out, then you can hook to the booster if you dont need modes or hook to the FET if you do, the booster would run the same either way (at full power) you just leave off the MCU and FET if you want single mode, should cut the price per unit in half for a single mode only.

As for the MCU, I really like the idea of using a tiny10 for AVR and a 10F322 for PIC, they use the exact same pad's / pinout so you can just choose which you want with it ONLY requiring that part to be changed, it wont fit anything like the new UI's I've been doing recently but a simple 2-6 mode UI with configurable memory and maybe a hidden strobe or something. Only thing the voltage monitoring would be handled differently between the two, we'll have to figure that out.
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: WarHawk-AVG on August 21, 2014, 04:31:11 AM
Yeah, those Tiny10's are nice...does it require a special programmer,  and/or would a programming board like I made for the Tiny13 work?

So we just need to build the booster, design in the Tiny10 w/ FET and go from there.

Think you can whip up a schematic?
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: Cereal_Killer on August 21, 2014, 01:29:29 PM
Our regular USBASP's will do them. I like the tiny10 cause it has an EEPROM, (the 10f322 doesn't). I don't know if there's a clip for it but yea you could do it on either a programming board like your 13A one or could do it ISP with a pin style connector.

What sort of solder less connectors do they make for tiny stuff? I know they have those little single-pin-leg clips,  is that the only QD option?
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: Cereal_Killer on August 21, 2014, 03:00:16 PM
Disappointing news-

2.8A is the max switching current, the input, max output is going to be under 2A and that's really taxing it, most likely we'll see about 1A out, the good thing is we can for sure parallel drivers to get more current out, I'm hoping we can parallel the 3410's on a single driver too.

so far the plan is-
ATtiny10
LM3410
bank of 2-4 0805 Sense resistors (yea I could use one larger one but 1206's arnt cheap and I dont have hundreds of them in every value like I do 0805's)
P-FET for polarity protection (should have lower dropout than a diode)
Necessary CAP's and resistors
inducer
some sort of schottky or zener diode (for over-current protection, without this powering the driver with no load connected will = bad things)


Brian (anyone else) I know how to do copper pours / vis's to dissipate heat from components neutral pad's, what can I do to try and dissipate heat out of the sense resistors with very limited space?


End goal is a single side 15mm driver (resistors can go on bottom with batt+ spring pad but nothing taller than spring. As usual would really prefer programming hookup's on bottom (be it the MCU its self or some sort of pad's / via/s).
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: WarHawk-AVG on August 22, 2014, 07:04:18 AM
copper pours, just draw a polygon, anything inside of it automatically fills in

I wish they had polygon pour for a circle, would be nice to have a solid copper base for the heat to evenly spread and dissipate
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: Cereal_Killer on August 22, 2014, 12:58:19 PM
Yesterday I mentioned this to Matt and he said he was a huge fan of the LM3410, he sent me a few .sch's he's used before. He so said the plan to use a FET was overkill, we could do everything we want with only then 3410. Didn't have time yesterday but will be checking out his files today and seeing what I can come up with. I also donated $5 to that LPF driver and included my email and some questions hoping to hear back but didn't.
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: Cereal_Killer on October 14, 2014, 04:29:14 AM
(http://i.imgur.com/lh1s066.jpg)(http://i.imgur.com/QPZ8pVw.jpg)


I dont know what happened, jupiter was in the right position or something but last night I decided to spend a little time on this doing math to pick out parts and shit and all the sudden today out of nowhere Warhawk PM's me, he's found some dude named schizobovine on oshpark / github and he's pretty much doing the exact same thing right now so I checked out his stuff, modified it to work with my already picked out parts and MCU and I have a .sch for a SEPIC converter and am getting everything laid out on a 17mm board tonight. I think it should even be able to go smaller for AA diameter lights but I might need to switch to a bank of 0805's or 1206' (actually I might do that anyway, its probably cheaper than those huge high power resistor's, they're like $1.25 each!)

So I ended up placing pad's for the Bovine dude's 4.7uH inductor's (which are probably good enough and they're tiny) but I had calculated that 6.6uH would make for smaller LED ripple (but this isnt gonna be high current anyway so "good enough" is probably more than good enough) tho better efficiency is always a good thing. Also being SEPIC this will allow for 2*NiMH threw 1*Li-ion input with about the same efficiency and even allow 1.8v (1*L91) use tho efficiency (and possible output, depending on what you had it set for) will suffer some. I dont know about 1.2v (1*NiMH), just have to wait and see. Ideally you would feed it 3-4.2v.

Note this is a CC regulated circuit but still dims via PWM. Think of SEPIC as buck-boost but with a much smaller input range (and better efficiency over that range). This can drive 3v emitters - 9v (including 1x MT) but its better to run 2* or 3* 3v emitters in parallel than it is series for triple builds [6/9v out will probably require zener diode change].

Think of the options for a 3Vin driver and CR123 builds for the muggles that can still take 16340 without issue and can even be used with 2* and 3* AA lights (like say mini-mag's). Plus you can do single-AA /AAA sized builds for 14500 /10440 and have the avalibility to run off the shelf L91/L92's for emergencies / spare's you leave in your car (and possible even NiMH).
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: MRsDNF on October 14, 2014, 05:09:47 AM
Sounds orsm. The reason it sounds orsm is that I dont speak or understand Chinese. This would be the holy grail of drivers if it went down to .9 volts. :)
Good stuff and keep it up.
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: WarHawk-AVG on December 10, 2014, 09:58:57 AM
Been a while since I have been here or futzing with flashlights

Sorry for not coming by sooner

Started a regiment of testosterone shots and it IS giving me alot more energy and drive...just gotta get over the "get off my fat lazy ass" modes :(

Any headway on this C_K?

Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: Cereal_Killer on January 15, 2015, 07:42:35 PM
Update finally. Boards are ordered. Plan is for a driver configurable (via sense resistor) up to 2.8A (possible see 3 if efficiency and life time expectations are lowered) from 2AA ALL THE WAY UP THREW 2s Li-ion! (Yes you read that correct- Input voltage from 2.4-8.4v) while doing the full outout and it should also do ~1.5A at 1.2v in (with single 3v LED)

It's also got the possibility of being able to drive 3s 3v emitters or even an MT-G2 (or any emitter / series string up to 12v). Tho that 3A out is a hard limit.

It's a SEPIC and I have selected components putting efficiency at the front of the wish list. When operated within spec it should provide >90% efficiency and should be able to do no <70% @ 1.2vin (with reduced output current)
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: Cereal_Killer on January 15, 2015, 08:57:08 PM
(https://644db4de3505c40a0444-327723bce298e3ff5813fb42baeefbaa.ssl.cf1.rackcdn.com/uploads/project/top_image/4b1q1LHp/i.png)


(https://644db4de3505c40a0444-327723bce298e3ff5813fb42baeefbaa.ssl.cf1.rackcdn.com/uploads/project/bottom_image/4b1q1LHp/i.png)
Title: Re: Lets build a 1.2-5.5v driver that takes a 13A
Post by: WarHawk-AVG on January 16, 2015, 10:22:17 AM
Daggum!!!!

I knew if anyone could whip one up it would be you!

Rock on man!!!