Driver for the MT-G2

The ideal is, of course, always sold out here.

The overdriving one, is more expensive and needs substantial heatsinking, I would imagine.

FT has a 5 mode version:
http://www.fasttech.com/products/1612/10001998/1143104-2-3-lithium-5-mode-3a-led-flashlight-driver
LCK-LED has a similar/identical driver with just Hi/Med/Lo (also it is the same driver as KD’s “Super Output” buck driver)
http://www.lck-led.com/19mm-3000ma-driver-modes-p-501.html?cPath=135

I do wish FT would stock a 3 mode version.

b3flex for 3000mA

h6flex for up to 6600mA

Probably the best drivers out there.

3-3.5A is just not enough. And it's 3-mode! ...what? Stop looking at me like that...

Any buck driver rated for the voltage you will be supplying should work fine. The closer the supply voltage to the vf the better. The 6v mgt2 vf climbs as the current climbs. So more than 7v if going over 3 amps. I have used that cheap 3T6 from Manafont with great success. Drives around 4.5amps stock. That was with 2S 18650’s.

Right now, I’m using just straight 7135’s with manual switches to control current and have 6S nimh cells. So 7.2v total. The cells are 4/3AF’s. Works great.

Don't forget the HBFlex... the only 3-amp-capable boost driver I know of - but the low end of the input voltage range is too high for a single cell (too high for two cells, really, though you might be able to get by), which is a shame.

Does anybody know if the TaskLED drivers, specifically the H6Flex, can survive with LEDs in parallel? I know that's the 'wrong' way to do it, but it usually works fine in the non-theoretical real world.

the driver won’t care about the LEDs wired in parallel, although the risk of an imbalance in Vf and current draw between the paralleled LEDs increases with current I believe. That’s just theoretical though, I’ve no practical experience of it.

So, how do you calculate total/individual amperage with LEDs in parallel run off a common output? For example if I used the H6Flex in the triple MTG2 build with 4S cells and LEDs in parallel, vs. the original plan which was HBFlex boost driver with 4S cells & series LEDs.

(numbers with the HB boost: cell voltage 12-16.8v in, total series Vf of ~18.9v; w/H6 buck: 12-16.8v in, parallel LED Vf of 6.3v)

I have no measurements at all as I have only just got my pill together with driver and led but can confirm that this driver will run the MTG-2 hooked up to a couple off trustfire 26650 at 3.8 volts with no load on them. The led is direct to copper and it is the quickest I have ever had a pill get hot. The mode changes still has that pause between them as reported elsewhere.

Cells in series or parallel? I have one of those drivers on the way, too.

Series.

Crap! :( Was hoping for some actual single cell boost action. Was it you or somebody else who reported that driver didn't like running off a single cell?

I just tested with 2 and 3 cell and now you want 1 cell tested? Ok, you sorta asked nicely. Be back soon. It is cold out there. :wink:

This is some really quick testing on the above driver with new Trustfire Flame protected 26650. Good news first.

3 cells 12.48v No load voltage 2.55 amps at the batterys current draw
2 cells 8.34v No load voltage 3.2amps at the batterys current draw

1 cell. No load voltage 4.15. On high battery voltage dropped straight away to 3.74v. Current reading I managed to get was 4.2 amps. Driver immediately dropped to a current draw off .4 amps with a voltage at the battery off 4.11v.

I would suggest this driver for some reason with one cell hits the low voltage cut out on the driver and drops to a lower mode. I dont believe l have enough time to get the correct current reading as this happens very quickly.
This also happened on an XM-L but just not this quick. The experts can chime in off which I am far from but this driver does not run well if used on high with a single led full stop.
If someone can work it out from this information it would be nice to know what current this may be getting at the led.

On an XM-L2 this driver on higher at the tailcap was running 1.39 amps with 4 TF 26650 which should be about 5.56 less efficiencies at the led.

Oh well. I suppose it would've been a minor miracle if it worked. I wonder if it works in boost mode at all (not asking you to run more tests, just thinking out loud!! lol) and under what circumstances. 8.4v in, total Vf of ~9v, 12v?

I'll have one to torture myself someday, that is if SingPost ever decides to look around for my package that must've got dropped behind a shelf somewhere and actually put the damn thing on the airplane... grrrr

I’d like to build an MT-G2 light that runs off two 18350s. Need advice, and a driver.

Which cells, & how much drive current?

This Host
These Cells.
I’m undecided on the current. Looking for advice on this setup.

Direct drive from 2x 16340s I got 3.6A, but it falls to 2.5A after only about 30 seconds (and keeps falling, and falling...). The little cells really don't like it...

I guess if you could keep the current down to like 1.2-1.4A it would give you more runtime before the driver throws in the towel, but what's the fun in that? A hard driven XML on a single cell would be brighter and run longer. If we ever get ~2000mAh 18350s this'll get a lot easier. :(

That’s what I wanted to know…if it was worth the bother, or a waste of money and time.