Hello guys, I seem to be in a dilemma. Got a Blackshadow Terminator Clone with basically a weak driver. I have added and removed some resistors here and there, but it's still not putting out nowhere close to what I want. Here is what I have and what I am looking for:
What I have:
- 4x XM-L2 with each led having it's own individual wiring
What I am looking for:
- The most powerful driver that can run each XM-L2 around 4-5 amps each. Either I can ready-made, or I can build it myself if need be (with some help of course!)
- preferable 46mm - I don't mind piggybacking off the orginal driver board if I have to, but only as a last resort
- Max height 12mm
- Would be nice to run JohnnyC STAR Advanced Momentary firmware if possible, not neccessary though
- preferably individual LED soldering points, like in photo below. I don't mind wiring in LED's parallel if I have to for only 1 solder point, IF I have to, but would like that to be a last resort.
After looking at all the SRK drivers people designed but never became available yet over the past 6 months, I am open to any and all suggestions, from buying a ready-made driver to building it myself.
This is the driver that came my light in stock form. I already moved one 1R0 resistor from channel 2, and added one 1R0 to channel 1, but still not as strong as I would like.
How about the one that people designed and actually got built?
http://oshpark.com/shared_projects/JV9IGc08
You have pretty high resistance on your existing driver (.25 ohms on one bank and .5 ohms on the other 2 banks). You have a lot of room to decease the resistance more.
If you do not need to have each LED on it's own circuit, Comfy's driver seem like the best option that I'm aware of.
And that stock driver is using wimpy little toy SOT-23 FETs.
How many do you want? :)
Thanks Comfy, I been following that oshpark thread, but its so discombobulating reading all those post, like 20 conversations about so many different boards all going on at once making it very hard to follow!
I see I can order 3 boards for $17 shipped. Do you have the digi-key or mouser cart order link that has everything already added for this board? I know I read about it somewhere, but have no idea where to find it now. Used the search and I am stumped!
Which channel do I need to decrease resistance on? And would I be adding or removing those 1R0 to decrease? I'm still a driver mod newbie, so nay help is appreciated.
You will sell me some already populated?
Edit added: Where is that baby SOT-23 FET on the stock board at? I don't see any FET's! Also, I ordered that 10 pack of Vishay 70N02 a few days ago, should be delivered today! Can I swap the that SOT-23 out for the 70N02?
Remove all the resistors and replace them with copper. They aren't sense resistors, just simple limiting resistors. Any current to the LEDs has to go thru those silly resistors too. Get rid of them. The little toy FETs will still give you more than enough resistance to keep anything from melting.
Digikey list for the BLF-SRK: http://www.digikey.com/short/9487m (make sure there's nothing in your cart already before clicking that, it'll add the stuff in the list to whatever's in the cart already)
I'll send you one built & tested for basically my cost plus postage, since the firmware isn't mine and I couldn't write my own from scratch to save my life.
Just added to my last post. Please check.
What firmware does that one your gonna sell me have? Price?
So for my current driver, I just remove all the 1R0 and copper solder the where the 1R0 was instead? Should I replace that SOT-23 since I'm getting the 70N02 in today?
Yes on the copper instead of resistors as Comfy said. You can also just solder the copper on top of the resisters to save time.
The 70N02 has a different footprint and pinout. You would have to do some creative "Comfy" type mods to get it to work on your board.
I have a Black Shadow Terminator and just removed the resistors, bridging the pads with a solid copper wire soldered in place of the resistors. With Efest 35A cells and XM-L2 U2 1D emitters on Noctigons I'm seeing start value's around 4500 lumens and 4300 at 30 seconds.
Couldn't I just add some legs to the 70N02 and then solder the feet to the correct pins. Would I have to replace all 3 of those micro SOT-23 FETS?
Comfy, would I be correct guessing that mattaus driver pushes 20A max?
Ya, after taking apart my clone, I realized that it seems like this BST host has amazing thermal heat dissipating properties, since there is no pill whatsoever! And I hate to admit it, but I swear my BST clone has become my go to for using on just about everything. Something about that handle, that makes it the most comfortable flashlight ever to carry, as well as never have to feel any heat. It barely gets hot as it is, because of its pill-less design!
I'm aiming for hopefully between 5500-6800 lumens, if each XM-L2 is run at 5A correct (around 1500-1700 lumens per emitter on Noctigon XM-L2 U2 1D).... Did I calculate that correctly?
blfdemigod wrote:
Couldn't I just add some legs to the 70N02 and then solder the feet to the correct pins. Would I have to replace all 3 of those micro SOT-23 FETS?
Possibly. I tried to do a quick Google for the pinout for that part, but I keep pulling up a switch. The size difference is large. You may need to use wire or something.
I would think all three would be the best way to go. Imagine that the driver will really kick ass if you do that. Please keep us posted if you do.
If the stock driver doesn't have a decent usable UI, don't bother. Bridge the resistors and call it done.
The FETs are the three 3-legged things marked 'A2SHB' and are the same size as the resistors! Datasheet here: http://www.s-manuals.com/pdf/datasheet/k/i/ki2302ds_kexin.pdf The 70N02 is massive in comparison, around 1cm x 1cm.
Can you link us to more info about that driver? I’m like blfdemigod- too many posts in the oshpark thread to keep track of.
Why do some of your driver pics show a coil, and some show a jumper where the coil was?
Also, the stock MCU might not even be capable of driving three big TO-252 FETs at the same time. The SOT-23s are a light load and designed with size and fast switching the priority, at the expense of max power handling & on-state resistance.
The inductor is only there to lower the low modes more than what you can get just by using very low PWM values in the firmware, while having very minimal impact on the output in high mode (the inductor only presents a resistance when the load switches on and switches off - with a straight DC current like in high mode it doesn't do any of that). If you don't care about a really low low it can be omitted and everything will work just the same. Inductor just goes inline between B+ and LED+.
I have a ton of driver build threads to do when I get caught up with other stuff. Just remember there's more to it than just taking pics while building the driver and then writing it up, each thread will generate pages and pages of questions, too.
I was hoping the coil was a boost driver to run the LEDs in series and eliminate the need for PWM.
LOL no, it's just a simple direct drive driver, with an easily-programmed MCU. I mean, even with the (optional) inductor & flyback diode it's only got eight components on it.
Comfy , the UI on my driver is pretty decent, and has 5 second memory:
1st press - 1 LED on
2nd press - 2 LED's on
3rd press - All 4 LED's on
4th press - irritating strobe
Thats a good point about the MCU might not be able to handle the bigger FET's. I guess I could always try right?
Now as for that Oshpark driver you recommended, is that able to drive multiple MT-G2 as well?
And whats the input range, as well as the output voltage and max Amps that driver can dish out? does it have low voltage protect and reverse polarity protection?
sorry, if this stuff is obvious, I'm new to modding drivers at this level. adding 7135's is mostly what I did to drivers.