I’ll have to see what happens when it’s hard wired inside a flashlight. Now I’m torn between using the 5 or the 7 emitter driver in this light.
Thank Tom. You answered the question I wanted to ask you. I was planning to fill the boards with Fujik, but was going to check with you first.
I have tested the 7x and 9x drivers from KD a lot (the 5x and the 7x, I beleve to be the same driver), and I have come to the conclusion that these driver are not strictly output current regulated. Normally boost drivers will keep the same output current, but be more efficient when step up is reduced. I have not figured out exactly how these are regulated, but my emprical data suggests that when step up is reduced both output current and total power output goes up following the better driver efficiency. The downside is that output also sags when input voltage sags. In my j12 I use dedomed Noctigon MX-L2s, 7x KD 5 mode and three cells. It starts at around 4.1A on fully charged cells (MX-L2s demand higher voltage than the stock emitters), and it has survived a great deal of use. I have installed 6 mm copper under the pill to help dissipate heat, though. I have not yet tested this driver to drive three emitters from two cells, but I will very soon. 8)
Thanks for that GBD.
I too was thinking that the 5 & 7*XML driver are the same. The fact that TomE’s 7*XML driver didn’t react the same way that my 5 & 7*XML drivers did when adding a third cell makes me think that he might actually have been using the 9*XML driver.
I have the 9* driver on the way! and I’ll run some more tests when it arrives.
For the 7X driver, I think the differences between our two setups is reason - you have XML's, I have XM-L2's, you have 5 LED's, I have 6 LED's.
Actually, now I wonder if all three drivers aren’t the same and it’s just a case of how many cells you use. This LCK Driver is the same one and is good for 5 - 9 XMLs. Do you think KD has one big bin that holds the same driver 5-9?
You may very well be right about that, I just substituted a 9x for a 7x in a three cell 6x light to test this and got exactly the same drive current! 
The upper limit for the output voltage is different between the 5x/7x/9x.
So with the LCKLED driver it’s really just the 9x, which is capable of 5x and 7x?
I think the upper limit volage is really related to max step up from two, three and four cell voltage. The 7x does not really work well driving seven emitters from two cells as the 9x has trouble driving nine from three.
They will drive the claimed number of LEDs as long as they are XM-Ls, but not if they are XM-L2s. The higher Vf adds up to put the total over what the drivers can do. So with XM-L2s, you need the 9x for 7 LEDs, the 7x for 5 LEDs, etc. Just don't ask me how to drive 9 XM-L2s... :Sp
Wire them 3s3p, use a 9A buck driver from 4s voltage. Btw, I am aware that the MX-Ls they use in the multiemitters require very low voltage, and therefore work well driven by the KD, but you still need three cells to get a desent output from seven emitters, and four for nine.
Well, I decided to use the 5*XML driver to drive my five XM-L2 light. If it dies or doesn’t function well I’ll throw in the 7*XML version. I’ll post my results when finished. I have a few more 7 and 9 drivers in the mail, and I plan to do some experimenting with them. I’ve never built any boost driver lights before, so I’m entering into a new realm
That's going to be right up against the upper limit for that driver's output voltage (they claim 17v max). For them to really work properly the output needs to have enough voltage overhead for it to be limited by the current as set by the sense resistors, instead of being limited because it's run out of voltage. That's the condition that kills them.
Well, if it really is the same as the 7x, you should get 2.8-2.9A using two cells and 4.1-4.3A using three if they are fully charged. 
Comfy. I heeded your advice earlier in this thread about the possible voltage ceiling using the 5* driver. The thing is, I’m using it instead of the 7* driver because if I don’t try it, I won’t have any use for it at all. I don’t plan on getting any 4 x XML lights, and for three I’d use a buck driver.
Also I made a custom contact board for it. It’s soldered on real good, and won’t be coming off.
I proved without a shadow of a doubt the 7X driver is different from the 9X driver, as comfy is saying. Opening post here: https://budgetlightforum.com/t/-/23851 explains it all in summary. Quick summary:
1 - 7 XML/7X beast driver: high amps, runs nice, but only XML's on aluminum
2 - 7 XM-L2/7X beast driver: amps lower and drop in short time
3 - 6 XM-L2/7X beast driver: amps comes back up - runs nice!
4 - 7 XM-L2/9X beast driver: high amps - runs nice, awesome output!
Thank Tom. It’s good to have some hard data on these boost drivers, and thanks for the tip on packing between the boards with Fujik. I have one curing now.
I finished the light today.
It's a Securitying 5*XML 3 x 26650 torch. I swapped out the emitters for XM-L2 U2 1A's on Noctigons. All springs are double copper braided, and the emitters are wired in series with 20AWG Teflon. The driver is the KD 5*XML boost driver
Here are my tail readings using KingKong 26650 cells.
2 x 26650 Per LED
High - 6.48A 2.59A
Medium - 1.28A. 0.51A
Low - 0.11A. 0.04A
3 x 26650.
High - 7.11A 4.26A
Medium - 1.60A 0.96A
Low. - 0.22A. 0.13A
There's no point in even trying to check visual output as it a really sunny afternoon. I'll wait til tonight.
I stripped the original driver to use as a contact board, but when I checked, there were only two little pads to connect the driver. With the driver sitting on the wires and adhered and insulated to the board with fujik, I though the the hight might be a little tight.
I made my own board out of copper clad double sided circuit board. It shapes really easily with a sanding drum. Anywhere i didn't want copper, I sanded it off. Then i cut a hole in the center, so the spring soldered directly to the driver. To connect the front and back sides of the ground ring, I drilled holes, inserted six 20 gauge copper head pins, soldered and snipped off flush. Works great.
On the driver side, I placed the outer ground on top of the copper clad ground ring I left on my board. I flooded all around with flux and let the solder flow. This board is not coming off! It's also very low profile, and I believe, offers less resistance than running through a board and it's traces, and into a wire and back to another board.
I packed the driver boards with Fujik before it was installed. I should have taken a picture, because I made a very neat job of it.
Only some running time will tell the tale of this driver.
One of these http://www.securitying.com/securitylng-6000lm-5-x-cree-xm-l-u2-waterproof-extended-led-long-flashlight/ ?
Wicked. How does it handle the 20A+?
Yes. That’s the light I used. The stock driver was a next mode memory 5 mode driver that put out a total of 3.3A. In low, the PWM was so bad it looked like an old moving picture.
It’s daytime, so I’m not even going to waste my batteries. I’ll run it tonight to get a real indication of the beam.