Looking at a new FET, built 2 X6's from host

Looking at a new FET, built 2 X6’s from host up using everything the same except for the MOSFET, and found a pleasant surprise! It’s not a big difference, but I’m thinking in a multi emitter higher drain circumstance this new one will do even better.

2- Brand new Eagle Eye X6 hosts
2-17mm MTN FET+1 boards
2x all the FET +1 components to build a Bistro driver twice
2- XP-L V6 1A emitters
2- 20mm Noctigon mcpcb
2-identical springs
20Ga Turnigy leads the same length all around.
2- New Efest 2100mAh 38A cells

The two MOSFET’s are both from Vishay, the SiR800DP that I discovered back when we first started building FET drivers, with Wight’s guidance in what to look for. And I tried the SiR404DP at Comfychair’s urging, find it somewhat confusing, perhaps more sensitive to heat. And now this new tech SiRA20DP with a bit lower Rds On time.

Built up both drivers and completed the lights with no spring bypasses at all, started testing a bit…

SiR800DP…………………………………………SiRA20DP
5.49A on Turbo for 1449 Lumens………….4.54A on Turbo for 1393.8 Lumens
5.39A on Turbo for 1435.2 Lumens……….4.34A on Turbo for 1421.4 Lumens
Swap cells
4.76A on Turbo for 1431.75 Lumens………4.75A on Turbo for 1404.15 Lumens
5.68A on Turbo for 1442.10 Lumens………4.77A on Turbo for 1407.6 Lumens

5.33A average for 1439.59 Lumens……….4.6A average for 1406.74 Lumens

So the mean difference was the SiR800DP used 0.73A more current to produce 32.85 more lumens.

Then I went and bypassed the springs. Through board at tail cap and 20Ga all around.

6.08A on Turbo for 1904.4 Lumens……5.82A on Turbo for 1918.2 Lumens!

The emitters are old stock XP-L V6 1A’s, not the newer W2 or XP-L2 versions, so it was a big surprise to see 1900 lumens from these X6’s! As you can plainly see, the A20 keeps up with the 800 while burning less of the cell and at higher amps even surpasses the venerable 800 in output while staying below it still in current draw!

Now I just HAVE to build a triple and see what the new FET does with that! :slight_smile:

Thought some of y’all might like to hear this, it was an interesting afternoon anyway.

Thanks for checking it out…

Edit: Checked out what an Efest 35A would do, along with a Samsung 30Q, each reading had the cells fresh off the charger…

5.75A on a 30Q for 1814.7 Lumens………5.72A on a 30Q for 1852.65 Lumens
5.62A on a 35A for 1790.55 Lumens…….5.47A on a 35A for 1787.1 Lumens

So max Lumens was achieved with the Efest 2100mAh 38A cell. With the lower capacity of this cell, the new A20 MOSFET has that bit of savings in amp draw that will make a difference. Interesting anyway, still want to see how it compares on the higher demands of a triple…

Each of the two cells I used in testing were first charged on my XTAR Rocket at 1A rate, before every test. So all testing was with fresh cells and at-start quotes.

Nice test, what was surprising to me is even with the old fet from 5.3 it was 1439 lumens and only .7 amps more it jumped up to 1900 lumens. And the other one barely a amp more and extra 500 otf lumens. Besides a nice new fet. This shows me the important of spring bypasses on both ends of a light with a decent gauge wire

Edit looking at it again it sticks out even more after the cell swap it reached like 5.68 amps for 1440 then after the bypasses went like .4 amps higher to 6.08 for 500 more otf lumens

Nice interesting testing Dale. :+1:

That’s why I ran the test over and over, and swapped cells to see if there was a difference there. These cells have comparatively low capacity but they can deliver a lot of amps… reminiscent of the old Samsung 20R.

The wire bypass results surprised me, I don’t think I’ve ever seen 1900 lumens in an X6. I need to test some other top cells and see if that’s consistent or if it’s purely related to these 38A cells.

Good info and nice builds.

It shows how the new advances are making these lights much more efficient with all the new driver changes and things that are constantly being tested and tried , many of them from our very own right here on BLF such as yourself.

Get the new XP-L2 in one of those and you should easily get over the 2000 lumen mark I would think.

I wouldn’t think the FET has the ability to increase LED efficiency at a given current, particularly at 100% duty cycle. Maybe the output difference is due to another factor like the LED itself? Exchanging the drivers would maybe answer that question.

Impressive output in any case. :+1:

The two emitters came out of the same tape, side by side. As did all the other components except for the two MOSFET’s.

I have an SBT-70 in an X6 that’s pulling 15A and making 1611 lumens on 22ga wires. Wondering what it would do on one of these drivers with 20ga leads? Not that it’s suffering in the component list, it’s got an SiR404DP FET on it’s driver.

The spec sheet says that the A20 has lower Rds On time, so I was expecting a bit more from this one, but didn’t realize it would be through lower amperage and same or similar lumens. Might have to pull my triple XHP-50.2 apart and put this FET on the driver, see if I can get that 12,000 I was looking for… :wink:

Well close the blf x6 you rebuilt for me with the w2 emitter put up just under 1900 like 1870 or something. And you did 18 gauge wire with it. And that m1 you built was a few lumens shy of 1800 with 18gauge. So your definitely pushing record numbers for these small reflectors. This new fet might just break 2k in a x6. The xpl2 and your first gen fet broke 2k in a c8. Might be able to get like 2300-2400 lumen in that c8 with Ryan’s copper pill in it with the new fet.

Those 20r are good cells. I found a pack that was a display or wouldn’t charge a couple weeks ago pack still had new plastic smell never heard of the brand name. Only decent find in about 4-5 months. All brand new, my opus read 35mohms or lower never seen the opus show that low with any cell 30q, 25r, hg2 etc. They will be my Q8 cells with one cell to spare. I know charges arnt very accurate with that stuff. But it still stood out. Never seen below 40 on it before and that was a 25r

Speed4goal, pick up a couple of the 2100mAh Efest 38A cell and try them in your X6/M1… I bet they’ll nudge your lights up over 2000……

I tested a 30Q and a 35A on these last night and these cells didn’t quite make the output of the 38A.