Small (20mm) driver for a triple XP-G2?

Flashlight Modding and DIY Parts
3

That V10+ gets asked about every day.

4

Aren’t most (all?) of the comments about the ramping one? Is it the same as the non-ramping 5000 mA one?

FYI, I’m starting to get the feeling the at true DD (wire only, no driver) will be only way to get even close to 4.5 amps, and even then, only with the right battery, esp. with the space restrictions with the S5 host :(…

5

I also have a non ramping V10 I haven’t tried. I just use the ramping model in the non-ramping mode anyway, because I don’t like it. There are very few lights with really nice ramping. Magnetic ring with infinite adjustment is the way to go.

6

Ohaya. Give Old-Lumens a PM. He uses these triple optics all the time in Mini-Mags.(I have three). Mostly he uses Nichia219, but they have the same requirements as XP-G2. Some he direct drives, and others he uses a Nanjg with a couple chips added. I mostly run them off a 14500 and a dummy. One of them I run with three Eneloop, or four 3/4AAs, so one 18650 should be fine.

PS. If you talk to him, I need a driver for a 3 x XP-G2 series optic.

7

Hi,

Ok, thanks, I’ll PM him about it.

For the 3x in series, there’s this one from CNQ:

http://www.cnqualitygoods.com/goods.php?id=1391

It’s a boost driver, and I used it to drive a Luxeon 3up, so it output 9+V. Unfortunately, it’s spec’ed for 1000 mA, so XP-G2 would be somewhat underdriven :(.

Edit: I have a 3.04a driver from IS coming in with some 350 and 380 mA 7135s. I’ve never stacked them before though.

8

Hi,

I’ve been testing that 1st driver on the bench tonight, and despite the comments in this thread:

it looks like this driver (1st on my list in the OP) may be able to DD at high amps.

I am using a benchtop power supply (30V/5 amps), powering that driver, and have two XM-L class emitters in parallel (for now, just to see what the driver does), and it looks like that driver can output pretty good current.

Here’s what my jury-rigged setup (apologies for the mess) looks like. The power supply is the background, and I’m moving the clamp meter between the 2 emitters on separate tests, in order not to leave it powered on for too long and kill the emitters, since they’re not heatsinked… just floating in the air:

And, here’s when the power’s on:

With 4.5 amps into the driver, I’m seeing about ~2.75 amps through one emitter (the newer one) and ~1.7 amps through the other emitter (the older one), i.e., ~4.4+ amps through both emitters.

Again, this is with a bench supply, so to get that kind of performance with this driver, I’d need to use a battery that can source 4.5 amps.

9

I’ve made 1/2 dozen triples, XP-E2, XP-G2s and Nichias. I’ve used 7135 based drivers in all of them, mostly the KD V2 but two with Nanjgs. Depending on the host (heat shedding ability) I add 380ma chips.

I’ve been successful up to 5.3a with the KD driver and XP-G2s, haven’t tried pushing it any farther. Put’s out a lot of light for a P60 host.

10

Try those Panasonic 18650PDs. They’re inexpensive, and I’m finding them to outperform my Efest 18650 IMRs.

11

So it looks like I have 3 viable choices:

- The FT DD driver

- 7135-based driver with, say, 12 x 380 mA chips

  • Real DD

I have a couple of 3.04A 7135 drivers coming from IS, plus some 380mA and 350mA 7135s.

The 7135-based driver will probably be my 2nd choice, for a couple of reasons: (1) I haven’t stacked 7135s before and the way the UF S5 is constructed, I’m not sure if there’ll be enough room to stack 7135s. Those drivers have that small spring, so I’ll have to solder one of the FT “partition” boards on the spring to make a contact board, which means there’s no room on the battery side of the driver to stack. I potentially could add 4 7135s on the emitter side of the PCB though.

So, I will try the FT DD driver with the 3up XP-G2 after I do the reflow, and then see how that does in real life.

If that doesn’t provide enough output, I’ll try to add some 7135s onto the IS driver and see how that goes.

The real DD would be my 3rd choice, as I’d really like to have some modes.

Thanks!

Jim

12

I did more testing with the FT DD driver, and it’s weird.

When it was on the power supply, it performed as I described earlier.

However, when I hook it up to a battery (and I tried several, including a CGR18650, an Efest IMR, and a KK 26650), it behaves very differently. I am seeing much less current at the emitter.

So, I hooked the power supply up again, and what I noticed is that the emitter current only increases if the power supply output voltage goes above, way above, 3.6V - 4.2V.

It’s almost like this is a 2 x Li-Ion driver?

But, I re-checked the specs at FT’s website, and it definitely says “3V~4.2V DC” :(!!

EDIT: Stranger and stranger - I tried the driver with 2xEfest 18650s, and, it worked, or, at least, it didn’t blow up :)!

13

Just install it. Take a hit for the forum. :bigsmile:

14

I know, but when you say “install it”, what do you mean by *it”? Do you mean the FT driver?

If that’s what you mean the FT DD driver, then that’s what I’m planning to do, but I’m currently waiting for the XP-G2 emitters and then I have to reflow them (successfully) before I can try any of the drivers. I’ll post back after that, when I have a chance to try things.

Thanks,
Jim

15

Maybe tonight ill do a quickie single XP-G2 installation with the FT DD and two LiIons just to see what happens.

16

The XP-G2s should be here this afternoon, and so I’m planning to reflow them onto the 3up, and then test after that with the 3up XP-G2.

17

Subscribing as I'm curious to hear more on this FastTech DD driver. That driver is cheap, so go ahead and push it!

-Garry

18

I will. Also FYI, I posted a ticket at FT, asking about what I found, esp. the “being able to run on 2xLi-ion batteries” part. That shocked the heck out of me :)!!

EDIT: Here’s what I posted on the ticket:

19

Don’t you need to double your current reading when using two cells?

20

Hi,

I was measuring emitter current, using a clamp meter (see earlier pics), rather than tailcap current, so the current was actually what was going through the emitter(s).

21

I didn’t know that you doubled the tail reading, but not the emitter reading. I thought I was russling up some extra amps for you.

22

Hi,

I reflowed the emitters successfully, and after I hooked the 3up with the FT DD driver and 2xEfest batteries, something blew up, literally. It also apparently melted the joint from the negative lead to the driver when the thing POPPED. I measured 2.31 amps (total emitter current out of the driver) to the 3up before that.

I’ll be checking things out after this, to see what blew :(…

EDIT:

The 3up emitters are still ok, but I think I found what blew. The chip is circled - you can see the bulge, and also the chip is lifted from the PCB on one side:

I do have a question. Which is the negative pad:

Is it the one I labelled (A), or the one I labelled (B)?

I think it’s (B), the larger pad on the right, but on the driver I got, they soldered over the through-hole. Can anyone confirm that it’s (B)?

I have a 2nd copy of the driver board, but wanted to check first?

EDIT: According to the pics on the FT site, it’s the (B) pad, so I went ahead and tried the 2nd DD driver, and blew in EXACTLY the same way. So my theory at this point is that (a) I was testing with just two XM-L emitters in parallel last night, which probably was ok with 2xLi-ion, but (b) with 3 XP-G2 emitters in parallel, they’re probably sinking more current than the FT DD driver can source, causing that chkp to melt/blow up.

Oh well.

So I guess that I’m left with the other 2 alternatives, either a 7135-based driver with 12 380mA 7135s, or real/true DD (direct from battery to emitter).