KD's FX-35 driver investigation


0K. Two different versions. I believe the only significant difference between the two probably is the current sense resistor stack value, which determines the output current. Of course, in theory this means one could connect the 2.5A version to a 3-4S emitter board. This includes “12V” XHP50/XHP70 boards, XHP35s ofc, and… triples. Maybe we should ask Kaidomain to get a small batch of in-series 3535 triple copper boards, and mount on them a few 219Cs/219Bs/XP-Ls/etc.

This would push up the power output up to ≈25W, so I would not be surprised if it would dare to draw ≈9A from the battery (high drain cells advisable).

Well, there's little info on this, so just speculating.

Zeremefico posted some test data here: Post #10 in “XHP35 single cell driver FX35 @ KD”

I should point out, though, that further test may be required. He feds the driver with 4.2V of input, something which is a never met, easier to handle condition for the driver. For me, the stuff has to deliver in real world “worst case” scenario conditions. Between low SoC, battery internal resistance and other losses, I'd test it with a 3.1V input, namely to take a good peek at input current handling and efficiency.

Contributions welcome.

Cheers ^:)

Barkuti, any news on that?

In the GXB20-Thread finges found another interesting driver:

H1-A 20mm 3A 1-cell 5-Mode Boost Driver Circuit

The OP does not seem to actually have one of these drivers to test them.

Obviously not, true. All those drivers are not really a bargain, so I’d hesitate to buy and test them, too.

I believe the FX-35 1A is a 12 volt output

and the 2.5A is a 6 volt output.

I was looking at their H1-A 3A and H2-C 1.5A drivers. These have higher output plus better modes.

You would get 2000 lumen from an xhp35 and 2500 lumen from a xhp50 or xhp70. That’s not too bad.

I wonder if they have memory?

I just bought a Ultrafire F13 which is about as big as a C8, but uses a 26650 battery. It has room for a 22mm driver and uses a 20mm star.

I’ve got an xhp70 and an xhp50.2 on 20mm stars to try out in it. I’ve also got a OP C8 reflector that might work in it.

I’m wondering if I should buy that H1-A driver to run the above 2 emitters at 3 amp (2,000 to 2,500 lumen) or run a pair of 26350 batteries with a more common fet driver (2,500+ lumen).

I don’t know if the H1-A has memory and that’s important to me. I’m gonna wait a couple of days and see if kaidomain answers my email about it.

Hi Jason

This driver board does not have the mode memory feature.

As i am trying, i can run the XHP50.2 LED at more than 3000mA. And you need to be aware the over heat problem.

Thank you


Thank you. Do you work for Kaidomain?

So with no memory, does it always turn on in the highest mode?

Can you explain the over heat problem?

As far as I know, Ban=kaidomain :slight_smile:

Is it a small store run by only a few people? I always thought they were huge! Lol

I do not think kaidomain is very big, and it is all flashlight related, but perhaps Ban can tell more about it?

(off-topic: Ban, when will you have XHP70.2 leds for sale?)

JasonWW, the overheat problem is as follows: 3+A of current over a 2S emitter, which is about twice the power on the emitter board vs a more usual XM-L2/XP-L at that same current, besides driver and other losses.

There's probably little to no issue on a big torch, but if you try it on an SK98 clone, you'll know what it means.

Cheers ^:)

Okay, you mean emitter heat. I thought maybe the driver had overheating issues.

I’m not worried about emitter heat. I use my lights for security work where the longest turbo mode is maybe 30 seconds. Heat has never been an issue. Plus the F13 is a bigger than normal host.

If the H1-A just doesn’t function like I want, I can probably run 2 26350 batteries and use a fet driver for 6 volt. I’m not real fond of TIR lenses.

I wonder which is better with a xhp emitter?
Boost driver with not so great UI and 5000mah liitokala or
Normal fet with great UI and a pair of 2000mah 26350.

I think that Ban refers to driver heat though…

Hi Jason

Maybe i make you too worried about on the heat problem.

I don’t get too much information on the UltraFire F13 host. I just see the head size is not very big.

Since the driver can run as output voltage 6V to 6.8V @ 4000mA for the highest mode, you can image how many heat is generated from the driver and the LED.
(For my situation, i need to provide a stability product to you. I am testing for opening an hour by this host http://www.kaidomain.com/p/S025386.KL-S26-26650-LED-Flashlight-Host-145mm-L-x-32_5mm-D-for-Cree-XM-L-Black-1-set)

Therefore, i just recommend you to take a better heat dissipation.

Hi djozz

We are ordering the XHP70.2 LED from our supplier. It will be arrived very soon.

Thank you for your supporting.

Thank you

That is great news! :slight_smile:

I think your host is about the same size as mine, so I’m not worried about heat.

Is this a driver that you are making or do you buy it from another company?

Is the H1-A limited to 3000mA or 4000mA? I’m a little confused when you said the higher 4000mA number.

Does it always turn on in high (100%)?

Slightly off topic, as far as I can recall, Kai from KD and owner of DX (can’t remember name) used to run one site together, but they split up to KD and DX.
I remember that I read once on CPF that Kai is flashoholic too :wink:

Ah, you can tell by the assortment that Kaidomain sells, especially recently! :slight_smile: