# SKU 26106 5xCree 15W driver schematics + 12V mod



## HansV (Apr 21, 2010)

I'm not sure it this belongs here, but I will give it a try.

I have manage to reverse engineer the SKU 26106 5xCree 15W driver board from DX and made a schematic. I have also identified the switching regulator on the board, that's AS2001 from Anisem
Having done this, I verified that the regulator also will work fine for 12V battery voltage. The only modification needed is to change the value of the series resistor R4(marked with a circle) from 150ohm to 1Kohm. This is the large 1206 resistor marked "151". this is a zener shunt regulator, and will draw about 50mA with a 150ohm resistor and generate too much heat. It could work still, but I would not recomend it.
The switching reguator is spesified up to 15V, and the other components is not a problem. The only thing is that the input voltage needs på be lower that the output voltage for the LED's.
The switching transistor can handle 30V, and the peak voltages are actually lower with 12V supply voltage. The power dissipation should also be lower because the current is reduced.

If a driver without the 5 modes is needed, just move the LED- wire to the sense resistors (R1/R12). Then the mode switch is disabled.

Hope anyone else finds this useful. I was wondering if I could use this board on a 12V battery, and now I know

Edit
Here is link to the schematics, that I converted to jpg:
http://img511.imageshack.us/img511/3064/driverboard15w.jpg


A short discription on how it works:
- U2 is the controller/ASIC that is used to make the modes.
- R6/C4/C2 is timing for mode switiching
- R4/D3 is a 5V shunt voltage regulator
- U1 is the boost switching controller (AS2001)
- T1/T2 is drivers to speed up the gate switching and reduce switching losses
- L1/D1/Q1/C1 is the boost circuit
- D5 will limit max. output voltage when the LED is disconnected or Q2 switched of, to avoid overvoltage on Q1
- Q2 is the current switch to controll the PWM/blinking for the modes
- R1/R12 is current sens resistors, with a constant 0.5V drop
- C5/R11 controls the switching frequency
- R9 controls the output drive current on pin5
- C6 is reference voltage filter cap
- C7/R10 is soft start timing

Hope this will help someone. This is a nice and flexible circuit that easily can be modded


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## aurum (Apr 21, 2010)

:thumbsup: Pm send ...


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## TorchBoy (Apr 21, 2010)

Sounds like some good work. Thanks for sharing. What format are your schematics in?


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## mash.m (Apr 22, 2010)

hi,

i also done some mod´s on this driver. i often got problems with the charge-cap from the setp-up output section, so i always replaced it with a better cap from an old mainboard or so...







markus

p.s. why can´t you post the shematics here?


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## HansV (Apr 22, 2010)

The voltage rating on the output cap seems to be OK(20V), but I think the switching current is too high. That is probably the reason that it breaks. Good quality 25V capacitors or cheramic multilayer caps should do the trick.
I have now uploaded the schematichs on ImageShack, it was too late to figure out how yesterday when I found out that I could not post the pdf file directly here on the board.


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## HansV (Apr 22, 2010)

Post more mods or report other problems with this driver board here, and I will update the schematichs and the top post!
It's a good driver design, but the componets are a bit cheap(OK for 4$. Therefor it is usefull to know what tends to break so it can be upgraded in advance to avoid problems.

Possible mods is for example to make a constant voltage output regulator in stead of constant current. That is easy with this board, just replace D5 with a resistor and connect output GND to board GND

Other possibilities is to replace the mode controller(U2) with another controller circuit to get other modes. Just connect 5V, GND and the control signal to R3/Q2 gate. It works with 3-15V control voltage on the gate and does not pull any current other than through the pull-down (R2).

For higher output current it is possible to upgrade L1, Q1, D1, C1 and C3. If the switching frequency is increased, the value of L1 can be lower to reduce inductor loss.

The switching circuit can be turend completly off by disconnecting R9, with for example a switch or a transistor.

I quess there are other possibilities as well, to fit specific needs. The input voltage is always limited to 15V because of the switching regulator, but the output can be higher if Q1 is changed to a higher voltage MOSFET. Then it scould be possible to drive 6, 7 or 8 LED's. Driving 3-4 LED's should work fine without any modifications.


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## eprom (Apr 26, 2010)

I have a feeling  that switching regulater is Feeling Technology FP5138B or FP6201

http://www.micro-bridge.com/data/Feeling-tech/FP5138B.pdf
http://www.feeling-tech.com.tw/km-master/ezcatfiles/cust/img/img/10/fp6201v01-lf.pdf

Could you confirm this could be or not HansV


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## HansV (Apr 27, 2010)

I can't be sure, because the driver board manufacturer has removed the text on the IC, but it's not FP6201. The pins doesn't match.
FP5138B has correct pinning and functionality, but doesn't come in SSOP8 package.
I still think AS2001 from Anisem is the regulator used here, but there could apperently be others that is compatible/interchangeble. Then it realy does not matter witch one they have use, as long as we can understand how it works and modify it.

http://www.yasemi.com.cn/pdf/AS2001_Preliminary_080303.pdf


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## HansV (Apr 27, 2010)

*Simple mods for better performance*

As mash.m stated, the charge capacitor (C1) on this board is underrated and prone to break. I have now tested alternative capacitors for performance.
I found that when I replaced C1 with a 10uF ceramic capacitor(1210 25V X5R), the input current dropped 50mA (at 8V input). The reduced power was mostly burned up in the tantalium. Use two capacitors in parallel to get the same value as before if you want, it will reduce ripple but is't nessesary.
I also changed R4 to a 1kohm 1206 resistor, enabeling the board to work fine with 5-15V input voltage.
One more modification I have done was to replace the rectifier diode(D1) with two BYS10-45 diodes to reduce the diode loss. They have lower forward voltage.
Increasing the frequency by changing R11 to 6.8k(150kHz) or 5kohm(200kHz) also reduces the loss in the switcher. I simply soldered another 10Kohm resistor on top of R11.

Newark parts list suggestion:
10uF 1210: 10R6036
BYS10-45: 96K7236
1Kohm 1206: 53K1779
10kohm 0603: 52K8062

I managed to drop the input power with about 1W with these modifications, so it is easy to increase the efficiancy of this board.

I recomend eneryone using this board and have the skills to change the capacitor for lower loss and better reliability.
If the board will see more that 8V, I also recomend to change R4.
The other mods is not nessesary, but will increase efficiancy. Higher frequency will also give better regulation.


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## Techjunkie (Apr 28, 2010)

HansV,

Thank you for taking the time to post all of this. What value do you recommend for R4 if driving this from 8xAA NiMH? (~10V-6.4V over the discharge)

Also, do you have a recipie for increasing output current (to ~1400mA) to drive 4 XP-G emitters in series? Or is that asking way too much of this board?


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## HansV (Apr 28, 2010)

1Kohm for R4 works down to 5V, so you can use that. 470ohm would also work fine.
For 1.4A you will need 0.5V/1.4A=0.36ohm. Maybe 3x1ohm resistors in parallel works? R12 (the 4.7ohm on top) can also be changed to 0.68ohm.
I will test this when I can and see if the board can handle this. You should definitly change the capacitor C1 when increasing the current.

Edit:
3x1ohm in parallel for sense resistor gives about 1.42A drive current.
I have tested this with load similar to four LED's. It seems that the rectifier diode(s) gets to hot with this current. Measured almost 90 degrees C on the diodes with 6V input voltage. Put this inside a hot flashlight, and it may not last long. The transistor seems to operate fine around 60-70 deg and the inductor is only 35-40 deg.
You can try connecting two driver boards togeather and strap the control signal from one board to the other, that should work fine. Do you want the modes, if not it is just to connect them in parallel.
Another solution is to replace the rectifier diode with a schottky power diode that can take the current. A TO-220 package can be heatsinked to the flashlight.

Or you can just modify the board and see how long it lasts. It could work just fine. If you mount the board so it's not enclosed in the heat sink/LED mounting base it will ceep cooler. You can put it the other way around or mount it sideways.
Just get a spare driver board or two, so you can repace it if it burns up. The components that is stressed when you increese the current is Q1, C1 and D1. All these can be replaced to deliver a lot more current. Just monitor the temperatures when you test it. It will get warmest with the lowest input voltage.


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## HansV (Apr 29, 2010)

When increesing the current on this board, the regulation becomes unstable and gets a audible low frequency noise.
This is caused by radiation from the big inductor picked up by the board and interfreing with the current regulator. It can be fixed by moving the inductor away from the board like this:




This is a good modification it there is room for it. Now you also have the possibility to add a heat sink on top of the transistor and diode to cool it down. Small heat sinks for motherboards that is glued on should be fine. The inductor can also be placed vertically and the wires can be swapped or extended if needed.
This board now has a 10uF cheramic 1210 capacitor for smoothing and 3x1ohm parallel for current sense. Works fine, but gets hot at lower voltages.
Unstabillity in the regulator is not a big problem if you don't mind the noise, so this driver should work fine even without this mod.


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## Techjunkie (Apr 29, 2010)

Hans, awesome. Thanks so much.


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## Essexman (Aug 12, 2010)

I used this board with a DX 3×cree dropin in a maglite. I thought it best to try and heat sink the board. I remembered seeing photos from one of you guys using copper tube in a maglite which worked well. So I made something similar. The driver is soldered to the copper plate via the outer solder ring (neg). I cut a hole in the centre of the plate to clear the Pos connection.






The board is std with no modifications.

I measured the current draw on each setting to calculate the Run times. The times are based on using 2000mAh Sanyo eneloop batteries. 

High: 1.35A current draw = 1hr 29mins
Medium: 0.84A Current draw = 2hrs 22mins
Low: 0.43A Current draw = 4hrs 39mins

I run it on high one evening with fully charged batteries and got 1 hour 30 mins before it went into a constant flashing mode, which I believe is low battery signal. Amazingly the theory works!
The head and body of the maglite was hot to touch, but not too hot. I put a freash set of batteries in and it worked fine. A great little driver!

Question: What would be the lowest input voltage used on this driver? Could it run 3 LEDs from 3.6V (3AA or 3C) or 4.2V(4AA) ?


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## eprom (Aug 12, 2010)

Hi Essexman,

You can use it for 3*Cree setup with 3*Ni-Mh. If you made resistance fix on Mag.

Here is my setup's runtime using 3*D size Sanyo 4400mAh Ni-Cad in 3*D Mag. Cree MC-E wired 2S2P and driver set for 1450mA.






Offcourse 4*Ni-Mh will work better.


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## Essexman (Aug 12, 2010)

Hi Eprom, thanks for the details. I really like this driver, it has so many uses! 

Wow that's some current draw on your D cells!!


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## jspeybro (Aug 14, 2010)

HansV said:


> This board now has a 10uF cheramic 1210 capacitor for smoothing and 3x1ohm parallel for current sense.



Hi,

since all the components on this picture are visible, would anyone mind to mark the R4 that should be increased to 1kohm for extended voltage range, the 3x1ohm current sens resistors and the location where I should solder the led- wire to disable the modes?

This would be my first driver mod, so I'd like to be sure I'm doing it right.

Also, I'd be interested in a better quality schematic since the text is hardly readable in the JPG in the OP.

*edit:* seems the 'single-mode-mod' was already mentioned here so that is solved.
I also used a multimeter to measure some resistances. Is the 150Ohm the one that I should upgrade to 1kOhm?


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## jspeybro (Aug 14, 2010)

does the inductor needs to be close to the board, or can I extend the leads a bit and put it on the other side of a heatsink (as if there would be a 10mm heatsink between the board and the inductor)?

The inductor is slightly too large for the space I have.
or maybe I could get an inductor that is a little smaller?


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## MikeAusC (Aug 14, 2010)

Make the wires as long as you like - you're just adding a little bit of inductance to a lot of inductance !

But - 
- use at least the same diameter wire, so you don't get resistive losses.
- don't run the wires close to the electronics on the board - this can cause instability
- if the run will be long, twist the two wires around each other.


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## MikeAusC (Aug 15, 2010)

I need a Boost Converter to charge a LiIon battery with 16.8 volts from 12 volts - this module will be ideal - with the Mode switch bypassed.


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## Techjunkie (Aug 15, 2010)

MikeAusC said:


> I need a Boost Converter to charge a LiIon battery with 16.8 volts from 12 volts - this module will be ideal - with the Mode switch bypassed.


 
This module increases output voltage to whatever level necessary to provide 800mA of forward current. I don't think it would be safe to use it for charging batteries as it would surely overcharge them and keep on going until


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## MikeAusC (Aug 15, 2010)

*Re: SKU 26106 for battery charging*

Yes, I forget to mention I will be changing the Zener Diode D5 to provide voltage limiting at 16.8 volts.

It would also be useful for charging 2x18650's to 8.4 volts from a USB port 5 volt output, if D5 is changed to 7.9 volts - say 2 3.9 volt zeners.


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## ma_sha1 (Aug 16, 2010)

I wonder if the driver being heat sinked can be used to drive 7-up XPG ?

Blue shark was also rated for 5 Cree (XRE) & I used it to drive 7 XPG w/o problem due to XPG has lower Vf. Here is a link to that light:
https://www.candlepowerforums.com/threads/251539

*What is the max boosted volt on this thing? *
Did I read it right that Q1 says 30V? That should be enough for 7 XPG. 
I think the blue shark max volt was around 25V. 

It was pulling at jut over 3 amp on 3 li-ion/12v with the blue shark.

I'd like to driver 7 XPG on two Li-ion 8V, if works, it would pull at least 
4 amp, may be 4.5 Amp from two C Li-ion. 

*Can the board handle 4-4.5 Amp input with good heat sinking?*


thanks


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## eprom (Aug 16, 2010)

Hi ma_sha1,

You can use this driver to drive 6 XP-G's. I have pushed the limits for this driver. Max open voltage is ~21V but ~1000ma regulated maximum voltage is ~19V.

When pushing 6*XP-G with 1A, it will pull ~3.5A @7V from two Li-Ion batteries. With good heat-sinking it will handle this.






ma_sha1 said:


> I wonder if the driver being heat sinked can be used to drive 7-up XPG ?
> 
> Blue shark was also rated for 5 Cree (XRE) & I used it to drive 7 XPG w/o problem due to XPG has lower Vf. Here is a link to that light:
> https://www.candlepowerforums.com/threads/251539
> ...


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## Essexman (Aug 16, 2010)

ma_sha1 said:


> I wonder if the driver being heat sinked can be used to drive 7-up XPG ?
> 
> Blue shark was also rated for 5 Cree (XRE) & I used it to drive 7 XPG w/o problem due to XPG has lower Vf. Here is a link to that light:
> https://www.candlepowerforums.com/threads/251539
> ...


 
This is what I love about CPF, there's me looking for how low an input voltage this driver can take, and then there's you looking for how high we can take it!! 

I've no idea about the answer to your question, maybe one of the other guys will chip in, but if it does work I might have to make another maglite


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## ma_sha1 (Aug 16, 2010)

eprom said:


> Hi ma_sha1,
> 
> You can use this driver to drive 6 XP-G's. I have pushed the limits for this driver. Max open voltage is ~21V but ~1000ma regulated maximum voltage is ~19V.
> 
> When pushing 6*XP-G with 1A, it will pull ~3.5A @7V from two Li-Ion batteries. With good heat-sinking it will handle this.




To have one of the led not lit in a 7-up would bother me, that's not an option. 

How about this idea: 
I could drive 6 led with one driver, then wire the 7th led with an independent driver that goes to the battery directly.

So when On, all 7 led would be on, when change modes, 6 led will change modes while the 7th led would remain constant on. So the low modes won't be that low, I can live with that, at least no led goes to waste, do you guys think it'll work? 


If it would work, I'll make another 7-up on Mag 2C, probably using XPE R3 this time to get a bit more throw.


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## ttwhin (Aug 16, 2010)

Essexman said:


> Question: What would be the lowest input voltage used on this driver? Could it run 3 LEDs from 3.6V (3AA or 3C) or 4.2V(4AA) ?



I think i read somewhere that the driver is the same that sit in this http://www.dealextreme.com/details.dx/sku.35242

If this info help..
I did a test on the 5* R2 Module from DX on full with with freshly charged 3, 4 and 5AccuEvolution D Cell 10000 NiMH 

Measured at tailcap
3 in series 4,35 Volt, draw 2,2A = 9,5W
4 in series 5,70 Volt, draw 4,0A = *22W* (was up to 4,2A and decreased)
5 in series 7,22 Volt, draw 2,5A = 18W

Tested before with 1 Li-ion cell but i didn't measure Amp, works fine and approx light output visible is about 80% of full output.


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## eprom (Aug 17, 2010)

My Feeling was right. Switching Regulator is Feeling-tech FP5138


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## showlyshah (Aug 17, 2010)

nice job dude? Can anybody give some of these schematics
1. Single mode boost driver for driving xp-g from 1.2v ni-cad/ni-mh

2. Single mode driver which can give 2.8 amps for sscp7 c bin from 3.7v-4.2v 2000ma imr. 

3.single mode driver for xr-e from 2.4v (2*ni-cad).

Good if it use mosfets and other components and not using any ic's. 

Thankz in advance


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## HansV (Aug 24, 2010)

So you got one where the component text was not removed? Great!

I was only quessing on what I found that would fit physically and functionally. But other circuits can also be used, it is not nessesary the same on all boards.




eprom said:


> My Feeling was right. Switching Regulator is Feeling-tech FP5138


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## HansV (Aug 24, 2010)

*edit:* seems the 'single-mode-mod' was already mentioned here so that is solved.
I also used a multimeter to measure some resistances. Is the 150Ohm the one that I should upgrade to 1kOhm?[/QUOTE]


Yes, It's the 150ohm resistor! 1kohm works great.

Hans.


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## HansV (Aug 25, 2010)

Here is a photo where the 150ohm resistor R4 is marked, that should be changed to 1kohm. 
I have also marked the 22uF capacitor that should be replaced and the modification to remove the modes.
The red line shows where to put the black wire. Just move it from A to B and solder it to the sense resistor.


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## Fichtenelch (Sep 2, 2010)

So which modifications would you recommend to drive a bridgelux led with this driver?
Changing the charge capacitor C1 to 10nF. Change R4 from 150 Ohms to 1k for input Voltages over 8V. What else? I want to drive a bridgelux led with 2x26500 li-ions.


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## HansV (Sep 3, 2010)

What is the spesifications on this LED, voltage and current? What type?
What current do you want to drive it with?
With two 26500 cells you will have 6-7V input voltage. This is what this board is designed for. Remember that this driver board is only capable of delivering a output voltage that is higher or equal to the input voltage. It can drive 3-5 LED's connected is series.
With two 26500 cells you will not need to do any modifications on the board unless you are going to change the output current. You can do this by changing the value of the sense reisstor. But the 22uF cap can always be changed with a better 22 or 10uF if you have one laying around.

Good luck, and if you come back with some LED data I can give you a better answer.


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## Fichtenelch (Sep 4, 2010)

I'm not completely sure, but i'm thinking about either the bridgelux bxra-c1202 (up to 13.9V at 2A) or the C2002 with up to 17.3V at 2.5A. however, 2A would be enough i think.


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## Flashie (Sep 13, 2010)

This thread is awesome, nice work guys and thanks Hans for starting it up  I ordered a TrustFire TR-1200 from DX (sku 30683) running 5xQ5-WC leds. Sadly I got the "new" batch with the horrible driver. So the light is about as bright as my Fenix TK11 r2, and by far not as bright as my TrustFire TR-650. Would this driver be a good replacement, and would it be possible (good idea?) to replace the R4 to be able to handle the 3x18650 the flashlight is born with? Or should i settle with running it with 2x18650?

If someone would spend some time helping me mod this thing it would be greatly appreciated, I'm not super strong in electronics, but I guess with a little guidance it would be possible for me to end up satisfied with the TrustFire TR-1200.

Thanks in advance guys! 

Kind Regards,
Flashie

Here's a few pictures of the head, might get a tad stuffed? i guess i have to screw the "black part" off to completely dissasemble the unit?


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## HansV (Sep 13, 2010)

The driver should work fine for three 18650 cells and 5 LED's. You will have about 10-12V input voltage. Just increace the drop resistor R4 in the zener regulator to 1Kohm.
You don't need to do any other modifications, but changing C1 for a better capacitor is good for the efficiancy and life expectancy. If you want more than 1A drive current, you can add a suteable resistor in parallel with the current sense resistor. The you can have some more light, more heat and shorter battery life.


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## jspeybro (Oct 3, 2010)

Hi,

I changed the led- wire to the sens resistor to disable the modes, and replaced the 150ohm by 1K for the 12V mod (although not an smd resistor).
I also modified the inductor a little by unwinding the copper 1 turn to be able to move it out of the way for the little room I have available.
When I connect this driver to 2 18650's in series (I know, not 12V, but it is just for a test) and to a cree MC-E with the dies in series, the led only gets 400mA. Shoudn't this led get about 800mA?
Could it be that the driver is currently in the middle mode instead of high, and that it cannot switch to high because I moved the led- wire?
Or should I use an smd resistor?

thanks,
Johan


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## HansV (Oct 4, 2010)

You should get 800ma when everything work. If you bypassed the mode switch there is no middle mode, just on 100%. The modes is made by the MOSFET transistor switching the current on/off, but the current is constant when the transistor is on. If you moved the - wire on the LED to the sense resistor, the constant current is always on.
If you are not going to use the modes, just remove the 1K resistor. This powers the controller, but you will not be using this. It is not nessesary to increase the resisor value for two 18650 batteries, the driver is made for just that input voltage.
You need to check that the wires are connected correctly. Then measure the input voltage from the batteries and the output voltage to the LEDs. Also measure the current again.
You can also measure the voltage drop across the sense resitor. This should be 0.5V when the regulator is working. If this voltage is lower, there is something wrong. If the voltage is correct and you still get too low current, measure the sense resistor. Current should be 0.5V/resistor value, or 0.6ohm for 800mA.
Come back with your measurements if you do this and it still doesn't work and you still doesn't understand why even when you spend some time thinking about it.


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## jspeybro (Oct 4, 2010)

Thanks for helping Hans.

Something seems not right here.

I bought 2 of these drivers, so I can compare my modified driver with an un-modified driver.
These are the numbers:
voltage of the batteries(2*18650 in series): 7.91V
current going to the driver: 1.44A
current going to the LED: 0.40A
Voltage over the LED: 12.53V
voltage over the sens resistor: 0.25V
sens resistor: 1.4 ohm (didn't change this. measured while board was disconnected)
These last 2 values seem strange to me but is the same for both drivers.

For the unmodified driver I also checked the current to the led for the different modes.0.4A, 0.25A and 0.12A. (and there are of course the strobing modes), so both drivers seem to behave in the same way.

as for the 12V mod. I plan to use the driver on a 12V battery pack but it is easier to test with 2 18650's. I guess I can remove the resistor since I don't use modes with this driver.
I also tried to use 3 18650's in series (12.06V). This worked but with the same light output as the 0.4A.

could it be that I have a different batch with a different sens resistor? still the voltage drop is only half of what it is supposed to be so that would explain the 400mA instead of 800mA, no?


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## MikeAusC (Oct 4, 2010)

jspeybro said:


> sens resistor: 1.4 ohm


 
Measuring very low resistances can be a problem, because the resistance of the probe leads can get in the way.

If you connect the probe leads to each other, what resistance do you get ? Subtract that resistance from any measurements you take.


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## jspeybro (Oct 4, 2010)

if I connect the probes, I measure 0.6-0.5ohm, so that gives a sense resistor of 0.8-0.9ohm which probably has still some uncertainty.

what about the 0.25V drop over the resistor? I measured it again on the 2000 milivolt scale and measured 270mV.


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## HansV (Oct 5, 2010)

This was strange?
The voltage on the sense resistor should be 0.5V when the regulator is active, regardless of the actual resistor value. One possibility is that the regulator is pulsing with a 50% duty cycle, but this seems unlikely. You can control this if you measure with a oscilloscope. Resistor value is OK when you have 400mA at 0.25V sense voltage.
Another thing you can check is the reference voltage on the regulator chip. Pin 8 (COMP) is the reference for the regulator, and it always tries to reach the same voltage on the input pin 1. Measure the voltage on pin 8 to verify that this is 0.5V. Also measure pin1 voltage. Could it be a new batch of boards where they used another version of the chip?
Another thing that could be wrong is the oscillator circuit so you have the wrong switching frequency, but this is not likely and you need a scope to verify this.
Also make sure that you are doing the measurements correct, and that your test equipment is working. Verify this with another instrument if possible.
Strange that both boards is doing the same? 
You can also try to disconnect the LEDs be desoldering the - wire and measure the unloaded output voltage to make sure the protection zener is correct and not causing the problem.


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## jspeybro (Oct 5, 2010)

HansV said:


> This was strange?
> The voltage on the sense resistor should be 0.5V when the regulator is active, regardless of the actual resistor value. One possibility is that the regulator is pulsing with a 50% duty cycle, but this seems unlikely. You can control this if you measure with a oscilloscope. Resistor value is OK when you have 400mA at 0.25V sense voltage.


I measured the voltage drop again with a Fluke 77 IV multimeter from work.
Resistor measures again 0.8ohm, voltage drop 265mV.



HansV said:


> Another thing you can check is the reference voltage on the regulator chip. Pin 8 (COMP) is the reference for the regulator, and it always tries to reach the same voltage on the input pin 1. Measure the voltage on pin 8 to verify that this is 0.5V. Also measure pin1 voltage. Could it be a new batch of boards where they used another version of the chip?
> Another thing that could be wrong is the oscillator circuit so you have the wrong switching frequency, but this is not likely and you need a scope to verify this.


I have access to scopes at work so I'll see if I can measure it there. I'll also check the pin8 if possible.


HansV said:


> Also make sure that you are doing the measurements correct, and that your test equipment is working. Verify this with another instrument if possible.
> Strange that both boards is doing the same?


I measured it with 2 different multimeters, so nothing wrong here I think. voltage was measured as a positive value, resistor was measured in 2 directions to confirm that this gave the same value.


HansV said:


> You can also try to disconnect the LEDs be desoldering the - wire and measure the unloaded output voltage to make sure the protection zener is correct and not causing the problem.


This gives me 21.12V output voltage without a LED connected, compared to 12.53V when the LED is connected.

The input voltage was 7.9V which is lower than the output so that should be OK too I guess.


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## purduephotog (Oct 5, 2010)

I believe it was a driver company that discussed using a 1 ohm resistor in parallel with the LED to measure the output current. The voltage drop across the resistor, in mv, is the current.

I can't remember the exact test, but this was being done because the ripple in the output from the driver could confuse some multimeters.

Not knowing enough about CC drivers I wonder if a capacitor would help smooth out the ripple.


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## HansV (Oct 5, 2010)

If you measure with a scope you can see the ripple. Consentrate on the sense resistor. The ripple should not be large, maybe 10mV. But the problem can be defective smoothing capacitors(C1 on my schematics) or wrong value. The then the ripple will be large and the mean current wil be lower. This can fit your DC measurements.
Did you do anything with the smoothing capacitor? If not, you can try to change it. Ceramic multilayer is best, but you can use a tantalum from an old motherboard or something of the voltage rating is high enouth. 10-22uF is OK. Severqal others have reported that theese capasitors breaks, but is seems stange if both are broken on new driver boards.
I was wrong about pin 8. It is not the reference voltage, but the filtered output of the error amplifier. Should be about 450mV.
The frequency can be measured on the switching transistor or inductor. Can also be measure on the switching regulator output or oscillator pin.

Come back with your test results when you try with a scope or try to change the capacitors.


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## jspeybro (Oct 6, 2010)

I found what was going wrong... and found nothing was wrong with the driver.
I was using these crocodile thingies to connect the batteries to the driver. I noticed some flickering in the LED and checked the wires. These were getting warm. I then realised that I'm pushing 1.44A through these wires. I changed the wiring a little (2 crocodile wires in parallel) and the current to the LED went from 400mA to 710mA. Still not 800mA but it seems that I was using wires that were too thin for the amount of current  

I'll change the wires that I soldered to the board for thicker wires and hope that everything will be fine then.

I checked the voltage drop with a scope and when driving 710mA to the LED, the voltage drop over the resistor was around 400mV, so that is getting closer to the 500mV that I should have. 

thanks for helping me.
Johan


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## HansV (Oct 7, 2010)

I work with electronics, and often enough do theese kind of mistakes myself. That was why a asked you to check your test setup
710mA seems within the normal deviation you can expect from a DX product. What are you measuring the voltage and current with? Try a good digital multimeter that don't get confused by a little ripple current/voltage.
If you think you need more current, you can just decreese the value of the sense resistor by adding more resistors in parallel.


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## jspeybro (Oct 7, 2010)

I was measuring the current with cheap (10-15€) Elix LX-830B digital multimeter.

I'd like a little more current, but first I think I'll first change the capacitor to be sure (and because I don't have the right resistors to add...). I have some 22µF tantalum capacitors here that could be used. I suppose it matters how these are connected. On the original capacitor I see that 1 side has a brown stripe on the edge. Is this side the positive side?


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## MikeAusC (Oct 7, 2010)

purduephotog said:


> I believe it was a driver company that discussed using a 1 ohm resistor in parallel with the LED to measure the output current..


 
No, if you put a 1 ohm resistor in parallel with a white LED it will always have 3.5 volts across it and will always draw 3.5 amps and dissipate 3.5 watts.




purduephotog said:


> using a 1 ohm resistor in parallel with the LED to measure the output current. The voltage drop across the resistor, in mv, is the current.


 
To measure current in a wire, you need to cut the wire and insert a resistor. A 1 ohm resistor will drop 1 volt per amp. A 1milliohm resistor will drop 1millivolt per amp.

You'll have trouble buying a 1mOhm resistor - you could buy a Meter Shunt but they aren't cheap. You can make your own out of some wire, but to calibrate it you need to an accurate current source.


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## jspeybro (Oct 9, 2010)

Thanks for all the help. I mananged to modify the driver to provide 930mA to a cree MC-E with the dies in series . I modified the driver by replacing the capacitor, adding a 2.2ohm resistor in parallel with the sense resistor (710mA without the parallel resistor) and replaced the 150ohm resistor by 1K although I'm not sure this was necessary because I also did the 'only-high-mod'.
To get in in the housing of a green-force 10W HID head, I also had to modify the inductor a little, but everything seems to work as expected.


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## HansV (Oct 9, 2010)

Great! That is about the same power I am feeding the MC-E in my WF-501B. Fill give great light output provided you have good thermal coupling from the LED to the flashlight housing.


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## sacongo (Oct 13, 2010)

Would like to give this mod a shot to increase to 3x18650. I think i could change out a resistor but im a little confuse. Found some 1kohm resistors some are 1/4w and some 1w which one should i use? *


*


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## jspeybro (Oct 13, 2010)

I used 2 500 ohm resistors in series of 1/4W.


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## eprom (Oct 13, 2010)

Hi HansV,

Could you explain, "how can we make this board a constant voltage source" on the photo. And what is the math for calculating output voltage.

Thanks,







Note: I forgot to solder sense resistor before taking photo, sorry.


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## HansV (Oct 13, 2010)

jspeybro said:


> I used 2 500 ohm resistors in series of 1/4W.



You do not need more that 100mW.
Best is to get a 0805 SMD resistor that fits the PCB. If you use 0805 you do not need to worry about wattage rating, anything will do.


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## HansV (Oct 13, 2010)

eprom said:


> Hi HansV,
> 
> Could you explain, "how can we make this board a constant voltage source" on the photo. And what is the math for calculating output voltage.
> 
> ...



There are two ways of doing this.
First you can replace the zener diode next to the sense resistor with another zener that has about the same voltage you want on the output. Vout=Vz+0.5V. Vz in this calculation is depentent on the current, and not nessesary the same as the rated voltage of the zener.

Secund you can replace the zener with a resistor. Then you also need to put back the sense resistor. Vout=0.5v*(1+R/10k). The 10K is R8 in my schematic.
As an example, 330Kohm will give 0.5V*(1+330K/10K)=17V
How accurate this it will be is dependent on how accurate the 0.5V reference is and the tolerance of the reistors. Remember that the output voltage must be higher that the input voltage.


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## eprom (Oct 13, 2010)

Thanks HansV, did I understand correctly. If I use the second way I must have a good external 0.5V referance. If correct where to connect this referance voltage. 

Again thnaks for the help.


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## HansV (Oct 13, 2010)

No, the 0.5V reference is internal in the regulator. You just have to replace the zener with a resistor to make a voltage divider that provides 0.5V on the input pin for the voltage you want on the output.


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## sacongo (Oct 14, 2010)

Hans
If i run 3x18650 with out changing the resistor will the resistor just cook or am i in danger of frying the board? Could you give some information on removing the board from the housing. You mention its easy to damage it when trying to remove it.


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## HansV (Oct 14, 2010)

Running 3x18650 will probably be OK, but you will dissipate two times the rated power for the 150ohm resistor. It will be warm and could burn.
The zener will also have to high power dissipation(250mW), but not critical.
Just try it. If it breaks, by a new one or repair it. If it works, good for you


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## sandysim (Mar 20, 2011)

Hi 
I just received my order for SKU 26106 on 18 Mar 2011. From the looks of it, there has been some changes to the components on the driver board. Most apparent is the big 25V 100microfarad capacitor in place of the 22microfarad cap that was prone to failure. Another change is the 4R7 replaced by 10R resistor. Have attached photos




for those still interested in DX's 26106. 

HansV, thanks again for drawing out the schematic.

Old version (left)vs New (right)





Plan view





Notice 10ohm stacked over another.(I haven't gotten round to checking what the rating of the resistor under the 10ohm one is yet.)


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## sandysim (Mar 20, 2011)

Hi Flashie

from the picture, it looks like the LEDs are wired in parallel. SKU20330 might be more suitable than 26106. 




Flashie said:


> This thread is awesome, nice work guys and thanks Hans for starting it up  I ordered a TrustFire TR-1200 from DX (sku 30683) running 5xQ5-WC leds. Sadly I got the "new" batch with the horrible driver. So the light is about as bright as my Fenix TK11 r2, and by far not as bright as my TrustFire TR-650. Would this driver be a good replacement, and would it be possible (good idea?) to replace the R4 to be able to handle the 3x18650 the flashlight is born with? Or should i settle with running it with 2x18650?
> 
> If someone would spend some time helping me mod this thing it would be greatly appreciated, I'm not super strong in electronics, but I guess with a little guidance it would be possible for me to end up satisfied with the TrustFire TR-1200.
> 
> ...


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## uk_caver (Mar 20, 2011)

sandysim said:


> Hi
> I just received my order for SKU 26106 on 18 Mar 2011. From the looks of it, there has been some changes to the components on the driver board. Most apparent is the big 25V 100microfarad capacitor in place of the 22microfarad cap that was prone to failure. Another change is the 4R7 replaced by 100R resistor.
> [...]
> Notice 100ohm stacked over another.(I haven't gotten round to checking what the rating of the resistor under the 100ohm one yet.)


I think you've been caught out by the SMD numbering convention there - '100' is 10x10^0 = 10R not 100R.
(I wonder, how many people _haven't_ made that mistake? I know I have.)

Possibly there's another 10R underneath to give a 5R0 total? or they've just been tweaking the value with a resistor a bit higher or lower than 10R?

Thanks for the post - I haven't used mine yet, but maybe I'll swap the capacitor before I do.


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## sandysim (Mar 20, 2011)

uk_caver

Indeed you are correct, my mistake. Should be 10ohm. I'll edit my previous post to correct it.



uk_caver said:


> I think you've been caught out by the SMD numbering convention there - '100' is 10x10^0 = 10R not 100R.
> (I wonder, how many people _haven't_ made that mistake? I know I have.)
> 
> Possibly there's another 10R underneath to give a 5R0 total? or they've just been tweaking the value with a resistor a bit higher or lower than 10R?
> ...


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## Techjunkie (Apr 4, 2011)

HansV said:


> You can try connecting two driver boards togeather and strap the control signal from one board to the other, that should work fine. Do you want the modes, if not it is just to connect them in parallel.


 
I understand how to wire two in parallel with the modes bypassed, as described in the other 26106 thread, but how may I strap the control signal from one to the other to allow me to run two in parallel and keep the modes?

I would like to mod two boards for 1.4A output each and run them in parallel for 2.8A max output on high, while keeping the modes.

Thanks in advance.


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## m.garlando (May 7, 2011)

I piggypacked the sense resistor R820 to raise led current from 600mA to 1,15mA on the new version! Now it pulls 2A at tailcap and the Q5's should produce at least 200 Lumen each and real 1000 Lumen total! 

Since heat management in the TR-1200 isn't the best, i filled up the gap between Pill and Body with Thermal Gap Filler Therm-A-Gap 976. I also did this with the driver. Heat dissapation now is consistant but it get's pretty warm after a few minutes up to 50°C and more. But it works well. 

I'm thinking to swap the leds to xpg's to get more output and less heat.









http://www.flickr.com/photos/pentaxo-san/5695642193/in/photostream


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## MikeAusC (May 7, 2011)

m.garlando said:


> . . . . i filled up the gap between Pill and Body with Thermal Gap Filler Therm-A-Gap 976. I also did this with the driver. . . . .



This material has a Thermal Conductivity that's one-thirtieth that of aluminium.

Rather that put up with this mess if you need to work on the torch, I would put in some aluminium brackets.


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## m.garlando (May 8, 2011)

That's right, it's appr. 6 W/(m·K)!

I tried it with wrapped aluminum foil. That did not work so well because small air chambers formed between the aluminum layer. The 

thermal gap filler material is flexible, compressible and has a high density, so there is no air in between. It feels dry and not sticky.


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## lautmaschine (Aug 19, 2011)

I also have one of the 'newer' boards fitted with the big 25V 100mF electro. It also has the 10R sense resistor, and underneath it is an R820. Do I understand correctly this would only drive 650mA?


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## tommydonovan (Nov 30, 2011)

Greetings,

I have this driver from dx. I seem to be having some problems with my setup. I have 5 Cree xml's in series. The driver is running off a 5*nimh cells which are around 6.5 volts freshly charged. The driver is drawing 31ma's on high and the LEDs are extremely dim. If I hook it up to 9v supply the driver will draw 70ma's and LEDs are roughly twice as bright. What gives? Thought this was 800ma's CC output? I have not measured current or voltage at LEDs yet as its difficult the way they are mounted. The driver should be able to drive them at 800 ma's as its rated at 15 watts and the LEDs Vf should be around 15 total in series. Any ideas on how to increase the current or is my Vi too low?

Thanks in advance,
Tommy


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## m.garlando (Nov 30, 2011)

tommydonovan said:


> Greetings,
> 
> I have this driver from dx. I seem to be having some problems with my setup. I have 5 Cree xml's in series. The driver is running off a 5*nimh cells which are around 6.5 volts freshly charged. The driver is drawing 31ma's on high and the LEDs are extremely dim. If I hook it up to 9v supply the driver will draw 70ma's and LEDs are roughly twice as bright. What gives? Thought this was 800ma's CC output? I have not measured current or voltage at LEDs yet as its difficult the way they are mounted. The driver should be able to drive them at 800 ma's as its rated at 15 watts and the LEDs Vf should be around 15 total in series. Any ideas on how to increase the current or is my Vi too low?
> 
> ...



Hi,

the unmodified driver should give you around 650mA to the LEDs on high. 
If your driver has no fault maybe your nimh can't provide the required amount of current?
Try with 2-3x LION 18650 to verify if the driver isn't faulty.

Regards

Roman


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## tommydonovan (Nov 30, 2011)

m.garlando said:


> Hi,
> 
> the unmodified driver should give you around 650mA to the LEDs on high.
> If your driver has no fault maybe your nimh can't provide the required amount of current?
> ...



I've had these batteries hooked to a different driver and single XML and pulled ~3amps or so. I'm wondering if the Crees are just too high voltage requirement?


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## wquiles (Nov 30, 2011)

tommydonovan said:


> Greetings,
> 
> I have this driver from dx. I seem to be having some problems with my setup. I have 5 Cree xml's in series. The driver is running off a 5*nimh cells which are around 6.5 volts freshly charged. The driver is drawing 31ma's on high and the LEDs are extremely dim. If I hook it up to 9v supply the driver will draw 70ma's and LEDs are roughly twice as bright. What gives? Thought this was 800ma's CC output? I have not measured current or voltage at LEDs yet as its difficult the way they are mounted. The driver should be able to drive them at 800 ma's as its rated at 15 watts and the LEDs Vf should be around 15 total in series. Any ideas on how to increase the current or is my Vi too low?
> 
> ...



If the driver is the more "typical" buck driver, then the total battery voltage has to be higher than the sum of the vf's for the LED's being used in series. So if you have 5x LED's in series, and we assume that each LED has an approx vf of 3.5V, then you would have:

output voltage (approximate) = 5 x 3.5 = 17.5 volts

You only have 6.5 volts from your batteries, so if the driver is indeed a buck driver, you are not even close to have enough voltage to drive your LED's properly - what would explain why you only see like 30mA or so.

If the LED driver is a boost design, then you would need a battery pack voltage lower than the load (lower than 17.5V), and it should work OK (although not very efficiently) at 6.5V input. 

However, I would still bet that it is more than likely that you have a buck driver, and that you would need at least 4-5 LiIon cells in series to properly drive 5x LED's wired in series.

Will


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## uk_caver (Nov 30, 2011)

The 26106 driver, which seems to be the one the poster has, is a boost driver.

Also, I'd be surprised that anything other than a boost driver would be able to put _any_ current through a series string of 5 white LEDs given a 6.5V source.
Much below ~2v5 per LED, it's likely that current flow and light output would be virtually nil.

Having any meaningful LED current and illumination would pretty much prove the boost nature of the driver in question, even if it would seem that there was something wrong with the driver or elsewhere in the setup.


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## jspeybro (Nov 30, 2011)

This is indeed a boost driver.
have you tried with a smaller amount of LEDs?
I have used this with 4 dies of an MC-E in series and worked fine (modded to be able to use 12V input). if it doesn't work properly, check all connections and have a close look at the driver to see if anything looks damaged or blown up.

maybe you can measure the voltage across the LEDs to check if the drivers succeeds in providing the necessary voltage.
Or you could ask for a replacement


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## wquiles (Nov 30, 2011)

OK, thanks for the clarification guys. So given that it is a boost driver, the problem/difficulty might be the wide gap between input and output voltages - the range might be outside of what the driver was designed to work with. I would try a higher input voltage and/or fewer LED's to see if the driver works better. If it doesn't, it might be that you just have a defective driver.

Will


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## Traum (Jan 24, 2012)

So this driver will run 3x 1w led in series and I can use more power from my NiMh pack when put them 7.2 volt(3xseries + 3xpararel). Current system runs 12volt (10 series) and I lost power cause cold weather kills battery cells., when bike is out cold when Iḿ in work. How about durability, is there any reports to seen failures with this one.

Have to test if I can use modes trough some kind switch... or just mod it away.


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## ledextreme (Oct 11, 2012)

Hi HansV
I received one of this drivers but appears to be different from yours, marked TR-0055C (rev C, may be), it have a electrolytic cap instead tantalum, I'm planing to make the mods for 12V, what you think about changing the lytic cap for the one you recommended? or should I left the lytic cap in place?
Thank you.


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## jspeybro (Oct 11, 2012)

what are the specs of the electrolytic cap? this is usually printed on the sides. It should have a certain voltage and capacity. Probably they replaced the original cap by a more decent cap.


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## HansV (Oct 11, 2012)

Probably a new batch. It should work fine as is, but the chermic cap will have much longer life and less loss. You can replace it if you like or when it breaks.


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## ledextreme (Oct 11, 2012)

The electrolytic cap is a 100uF 50V


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## ledextreme (Oct 11, 2012)

I tested the driver (new version TR-055C) and did not put the current published to the LED's (800mA), I'm using 5*Cree XML U2 bin, the voltage at the output is 13.89V and the current 615mA, I noted that the resistor is a 0.82 ohm which is almost in the calculation results (609mA), question, if I change the resistor to a 0.5 ohm, there is another change that I need to do to driver to support the current (1A)?, It have the D540 schottky diode and the MOSFET is a 40V 5A, the L1 is little smaller than previous revision of this board.

Thanks


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## mzxptlk (Nov 1, 2012)

Hi Hans,

thank you for your modding suggestions.

The link to your Picture of the reverse schematic is probably no more available.
http://img511.imageshack.us/img511/3...erboard15w.jpg

Could you please renew the picture?

Thanks


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## uk_caver (Nov 1, 2012)

I think that _might_ be an imageshack problem rather than anything else (maybe a damp or power-deprived East-coast datacentre?)


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## mzxptlk (Nov 3, 2012)

I hope Hans will forgive me ((((-;

Found his schematic drawing at
https://picasaweb.google.com/lh/photo/GHrpUWPk6T-1UpoHCv7jk9MTjNZETYmyPJy0liipFm0

:shrug:


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## Fozzy Vis (May 2, 2013)

Any chance anyone would have a higher res version of the schematic somewhere (or the schematic files for a cad program)?
Might be my eyes, but the schematic at picasa isn't really clear...

Anyone?


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## tinkerman (Jul 5, 2013)

Fozzy Vis said:


> Any chance anyone would have a higher res version of the schematic somewhere (or the schematic files for a cad program)?
> Might be my eyes, but the schematic at picasa isn't really clear...
> 
> Anyone?



I think the downloaded image is blurred on purpose to make download ineffective. If you press the magnifying glass button, you'll get better resolution via a flash plugin, but which won't let you download the better image displayed.


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## tinkerman (Sep 13, 2013)

Has anyone figured out what micro-controller is used in this board for mode setting? I want to program it with my own functionality and solder it right in, no piggy-back board or such.


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