New XM-L driver on DX, anyone getting one?

[DmitryCat]

i have new version too
anyone know, what a PWM controller(small chip with 6 pins) on this board?

[dinac]

2 VEGASf6 : is this tested in parallel or series connection ?

Or better qestion. it it better to connect 2pcs XML t6 in series or parallel ?

[moderator007]

Or better qestion. it it better to connect 2pcs XML t6 in series or parallel ?

Series, they both get the same current and voltage divides.

[dinac]

In case of connecting 3 xml-t6 in series will be more or less heat disipation from driver ? Like in case of this driver : http://www.simple-electronics.com/20...using-fet.html

[Techjunkie]

I just got new version of this driver :


it hasnt got that secon circular PCB on top like old drivers...

maybe someone has found solution where to tap resistor for full power ?
old PCB vs. new are different....

Any spec change with the new PCB? It'd be nice if the driver memory function were improved on the new boards.

[dinac]

no it is same ....

does anybody know where to tap resistor for full power pleaseee

[Packhorse]

I think ( only think) that the chip that does the PWM for current control also does the modes. As such I doubt it can be modified to single more.
I hope that I am wrong.

no it is same ....

does anybody know where to tap resistor for full power pleaseee

[Packhorse]

pic removed due to size.

As per the thread on the DX review....

Cut the pin from the IC marked in green. Solder a 1K resistor from the IC pad ( not the IC pin) to V+.

(This part is untested. Once the green pin has been cut you could put the resistor from the red pin to V+)

Thanks to Bitloader for the info!

I tried it at 10V and a single XML It drew 1 amp. 2 XML's and current went up to 2-2.2 amp

[VegasF6]

I tried it at 10V and a single XML It drew 1 amp. 2 XML's and current went up to 2-2.2 amp

That doesn't sound as though it is operating at a constant current. Have your tried at any other input voltages to see if the output remained the same?

[Packhorse]

To get more power out you must put more power in!

I never measured output current. Just input current. Always seemed to be about 10watt for a single LED and 20 watt for 2 in serial.
Based on this I would say its very efficient or not putting out 3amp. My guess its probably a little of both.

EDIT: Driver seems to be 2.7 amp not 3 amp according to previous posts.

[VegasF6]

I see. You can look at my measurements in post 33 for efficiency numbers from my testing of the prior model.

[Packhorse]

Ah yeah thats where I got the 2.7amp from. Thanks for that, Its a great chart!
On my current build I have decided to use one driver per LED so I can switch them individually.

In the pipe line is programming a ( arduino?) chip and have it switch 2 PWM outputs via one piezo switch.

[Thr3Evo]

wondering what wattage resistor is recommended for the mod

[Thr3Evo]

and also does said resistor go to V out+ or V in+

[Packhorse]

I used a 1/4watt to V+in. But I guess what you really meant was what impedance. 1Kohm

[Thr3Evo]

no I really meant wattage just to make sure I have everything covered. Thanks

[Packhorse]

There is next to no power travelling through that resistor. Any wattage rated resistor will work fine.

[Thr3Evo]

Cool, I was looking into driving other projects by resistor only and had to make sure I kept the power dissipation in mind there so I had to ask here as well. Btw the way I read it, the "untested" part is an alternative right?

[Techjunkie]

Packhorse, in your tests, did you solder a 1k ohm resistor from the red pin to the pad of the cut green pin? Or did you get V+ directly from Batt+? And is that mod to give single mode? Thanks.

[Packhorse]

As per the above post. Cut the IC pin.
Then the resistor goes from green pad (where the IC pin was) to V+
From what I understand the red pad is leads back to the green pad but I have not tested this.

[Breikin]

i just ordered this driver to use it with one xml ... one question remains: does it need a heatsink? if yes, where should the heatsink connect to the driver? thanks!

I also wondering where do you guys attach the heatsink ?

[Packhorse]

I also wondering where do you guys attach the heatsink ?

I have yet to use a heat sink or have heat related issues with this driver.


Another thing I have yet to do is connect to in parallel and run them at double current....yet

[langham]

Thanks for all of the information on this post it has really helped me out. I have had trouble finding a good 8.4+V driver that will drive at 2.7-3.0A consistently, but this one seems to work. I have planned a project that will use this driver and 2*18650 host with only a single mode. Do any of you know if this will eliminate the low voltage shut off? Does the 1kohm resistor act as a termination point in the circuit? I was also wondering if I could take let's say a SKU: 127684 from DX and add a transistor to it and use it as a 7.2-8.4V driver, and if so can one of you with a little more experience explain how this works (not only a picture saying solder from here to here but what it does to the circuit). I have one of these and like that the pwm is at a high enough frequency that you can not tell that it is pulsating, and it has many options including a high100% and low 5%.

[Techjunkie]

I'm not aware that 57779 has a low voltage warning, although if it did, I assume you'd have bypassed it when bypassing the modes.

On a side note, I needed to replace the driver in a two cell, single XML light that didn't have room for the height of 57779 or the width of 20330. I tried 106805, which was the only high current (2A) two cell driver I could find that was short enough and narrow enough. To my surprise, out of the envelope it put out 2.3A on high (unusual that anything from DX operates over spec) , measured with a clamp meter. After adding a 0.47 ohm sense resistor, it now puts out 2.7A on high and draws 1.33A from two IMR cells. I haven't run it on high for more than a few minutes yet, so buyer beware. My only complaint is the mode order: Mid-Low-High-Strobe-SOS, and the mode memory: if off less than 60sec, it will turn on in the next mode. I haven't tried it with more that 8.4V in or with more than one LED.

[langham]

I am having trouble with this mod. I did what the first picture showed and I wound up getting battery voltage to the led. Any reason the voltage regulation wouldn't work?

[Techjunkie]

I am having trouble with this mod. I did what the first picture showed and I wound up getting battery voltage to the led. Any reason the voltage regulation wouldn't work?

Make sure the windings of the coil aren't shorting out on any other components or the host and make sure the negative LED lead isn't shorting to ground.

[magudaman]

I recently got this driver to try to run my mag mod 4x xm-l units but the thing is heating up way to fast. I see around 2.5 amps going to my LEDs. I am thinking about changing the diodes out with one I can heat sink off. Any idea if the two diodes are just in parallel or serve a separate purpose?

[langham]

If you look further up in this thread you will notice that the efficiency does not really allow for 4*XML, instead you should use a different driver or use 2. I am having difficulty with mine still. Maybe it is explained on the picture which was removed due to size, would anyone mind posting that picture or a similar one up again, thanks.

[recycledelectrons]

Your search "sku 57779" did not match any products。

But, searching for "57779" will return exactly one result.

[magudaman]

If you look further up in this thread you will notice that the efficiency does not really allow for 4*XML, instead you should use a different driver or use 2. I am having difficulty with mine still. Maybe it is explained on the picture which was removed due to size, would anyone mind posting that picture or a similar one up again, thanks.

Well according to my testing the only thing on the board that was overheating was the two diodes and that was causing the board to reach crazy temperatures causing problems, my two diodes should show up today and hopefully I'll test it out and have it running to give an update. According to that chart the efficiencies kept improving each time he added an emitter. Really if I can get around 85% efficiency I am pretty happy, especially for a cost of 8 bucks.