Interesting. Looks like the clones are not using a true buck style driver like the original MS did. This appears to be a linear or PWM type.
Since the MS lights and most clones are using 7.4V batteries this must be PWM.
What is the voltage of the proper battery for this light? This will be one of the first steps needed to figure out what all might be damaged or figure out a replacement circuit board. There are only two things about using the wrong battery that would toast the light, wrong voltage or wrong polarity. Did you ever run the light using the proper battery?
Almost every one of the Chinese clone lights run on an 7.4v (8.4v hot) 4 cell battery pack, just like most magicshine lights. If you plugged a MS battery into this light, it shouldn't have blown anything up unless you have a weird pack that is more than 8.4v hot.
Hendo linked to the driver board that DX says fits most of their clones - but it is only rated at 1500ma current, which would never get a single XM-L to the claimed lumens - that's only half the max current rating of an XM-L. Could be possible that they never drive these hard to begin with, or they may have backed the current down to preserve the lights. You should still be getting ~500-600 lumen at 1500ma current - if - this driver actually gets there.
Hendo - thanks for the link though, hadn't seen that one yet. This should make a nice budget single XP-G2 driver.
This one is rated a little stronger. 5V~8.4V 2000mA 3-Mode LED Driver Board - Free Shipping - DealExtreme
I'm betting that stacking the sense resistor, one or both of these drivers can get up into the 2.x range for XM-L use. I think I'm going to order a few to experiment with.
The best option to drive an XM-L would be this one: T6 3-Mode Regulated LED Driver Circuit Board for DIY Flashlight (2500~3000mA 4.5~18V) - Free Shipping - DealExtreme I just used one of these in a flashlight mod, and it is really putting out about 2.4A - but it makes the XM-L look pretty nice.
Unfortunately it loses the momentary switch - I had a big plan of fixing an 808-style light for a friend, but getting around the momentary switch was going to be an issue.
I wouldn't think these are linear, with that induction coil, right? Also with the 2S working voltage spec and a single emitter, there's be a lot of heat tradeoff, and I just don't think these are designed to handle that kind of wattage differential.
Originally Posted by Vancbiker
I'm still interested in seeing if one of the board with the integrated switch can be hot-rodded up to suitable XM-L current levels.
I was referring to the board in the OPs light.
Originally Posted by adrenalnjunky
The DX board that HHiH linked to is a buck driver. The only thing I have seen be a real problem on these is the inductor is only attached by its leads. I have seen 2 of these suffer fractured lead due to vibration from riding. A glob of RTV or hot glue to tie it to the PCB is all it takes to prevent that failure.
Honestly, given the quality control, the OP's board may just be missing its inductor coil, lol.
The good news, is it is repairable, and now there appear to be drivers that will cooperate with it properly.
some of the more recent MS clones have been coming out with 1S4P packs (3.7V) instead of the original and ubiquitous 2S2P (7.4V) packs. If that's the case, and the driver looks like a simple linear driver (no coil or large FET), then plugging a MS 7.4V battery into this would fry something pretty quickly as the driver would try to burn off 8-10W of heat by dropping 8V or so down to the 3.2V of the LED.
A bit more info from the OP would help though - what's the capacity and voltage of the battery? Either one would do as we can infer one from the other, if it's a 4 cell. (square, weighs about 220g)
May be just a cable issue
Looks like a stray wire coming from the positive wire may have contacted that resistor and shorted it.
Good info to know!
Originally Posted by mattthemuppet
My thoughts too. The solder job on the red lead is horrible. It's why I asked if it ever ran on the correct battery.
Originally Posted by scar
The battery is reading 3.92V ... Ooops
Yeah it ran on the original battery.... but certainly brighter on the 7.4V battery. hehe. The craftsmanship is pretty rad on this thing indeed.
Originally Posted by Vancbiker
I'm not opposed to running a different battery with the repaired light.
The main transistor for the regulator burned up and shorted out due to the over voltage. It likely is a very simple PWM regulator. That's the burnt up black thing between the red and black wires. The LED itself is probably getting the full voltage minus resistive drops in the wiring and circuit board which is why it's extremely bright when plugged into the 7.4v battery. There's a chance the LED has suffered some damage as well. Depends on how long it ran on the 7.4v battery. I'm also surprised the over current protection didn't trip on the 7.4v battery, but then again it is a magicshine.
The micro-controller on the PCB wasn't damaged by the higher voltage and that's why the indicator LEDs still works. It will probably work if you replace that transistor, but figuring out what it is will be a challenge since the markings are likely burnt off. I could figure out a suitable replacement but I'd have to know more details on the exact circuit layout.
As others have suggested, it's probably be easier to find a replacement driver that'll fit the case. That would likely mean switching to a 7.4v battery.
You gotta love someone that designs a light that runs off a lower voltage than the light it copied and then keeps the same connectors.....
No kidding, I probably should have known better though. It was only plugged in for 3-5 seconds and it still works so hopefully its all good.
Originally Posted by MtbMacgyver
I have 7.4V batteries so switching out the driver board might be the best option. Then I wont have to worry about doing this again.
I guess I paid $30 for some housing and an XLM...
I'll listen to more suggestions but it seems like getting one of these5V~8.4V 2000mA 3-Mode LED Driver Board and running my 7.4v battery packs is the way to go?
That would get all of your light heads running on the same voltage battery.
Originally Posted by e-luder
then you can take the batterypack for this light, disassemble the cells and plug them into this holder: Battery holder: Li-Ion 18650 Battery Holder (2S2P) With 2.6" long 20AWG & PCB
That would give you one more functional battery that would work with your magicshines and this china light once you have the new board in.