17mm & 20/26/27mm single-sided DD/FET driver release: A17DD-SO8 / A20DD-SO8 / etc

Very nice Dale. Thanks for the video.

Whoah!

Now all you need to do is mod that for a quad XP-L and give it a go!

That’s a 20mm quad noctigon correct?

Measurement for that quad heatsink sir?

Awesome!

Wights FET driver (A17DD-S08) pushes 4 XP-L’s ridiculously hard. Not so much hard on the emitters, but cell draining and heat producing. So I used the XP-G2’s here for some limitations. It’s still pulling over 10A, but the Quad XP-L’s off this driver pull closer to 15A.

I must be getting old, I’m starting to realize there are times that 100% pedal to the metal is not appropriate. Sometimes 98% is called for. :stuck_out_tongue:

Ready to test mine,one on left needs lil solder removed but good to go i hope

One on the left looks backwards(mcu).

You are correct. I couldn’t make out the markings when I looked at the picture earlier today, but the Pin1 notch clearly shows that it’s spun around!

All fixed

Dale, you've got to stop making us all jealous with those lights you're building!

I'm "only" getting 5.85A absolute max at the tail with a A17DD-S08 in an X6 powering an old, good XM-L2 U2 1A on a Noctigon, using 20 AWG LED wires, bypassed springs. It's really hard to tell, but out of the 3 types of BLF 17's I used: v1.0 original BLF - Mattaus, the C_K v3.1 version, and the A17DD-08, the only one I could get over 6A out of was the BLF v1.0 originals. I did not compare these head to head -- all were in different lights/builds, so I can't be certain of anything, but really thought I'd get over 6A in the X6 with the 20 AWG wires, and the lock down retaining ring - seems to have a really good ground (batt -) path.

Multiple LED's is the easy case with low Vf's. The single LED setup is the worse case, but is the best real world way to test the resistance of the driver that I know of. I may have to build up a BLF 17 v1.0 just to see if it can do better. Why I need higher amps is not because of the domed XM-L2 U2 1A, but I'm getting a max of only 3.7A in the X6 (w/A17DD-S08, 20 AWG wires) with a de-domed XP-G2 S2. I have a Convoy C8 with a de-domed XP-G2 R5 that gets 3.95A at the tail on a 7135 based driver.

I saw your post about the XP-G2 over in RMM’s thread. I’ve been assuming that you’ve simply got LEDs with a high Vf.

You don’t really have to put them head to head IMO (although that would be ideal). Instead just measure the Vf with your DMM. If you compare the two XP-G2 setups and find that the Vf is similar between the DD setup @ 3.7A and the linear driver at 3.95A… mystery solved.

After seeing all the smiley faces from Dale-mode mods I sort of assumed that the FET had become a non issue but if it turns out to be the case that the FET could be improved I would gladly pop for 10 of the more expensive ones to spread around for testing to see if there is justification for a GB for enough of them to bring down the cost plus shipping.

im in for 5-10

I’ve got 24 boards on the way and a few left on hand. :slight_smile: I, uh, seem to go through drivers a lot lately. hahaha

Again, let’s not jump the gun. The datasheets clearly show the current FET in a good light, and as far as we know “better” alternatives are all more expensive. IMO the thing to do here is test with what we’ve got vs what we’re trying to meet/beat: the Vishay 70N02. An extra dollar or so per driver really is quite a lot. I’m not saying not to test the more expensive FETs at all, but step one is to see what we’ve got now!

I had bought 3 Convoy M1’s for comparing components before. I can use one of these to put an A17DD-S08 in and compare side by side to the 70N03 version driver. Shall I do so?

Edit: More or less they’re already set up that way. One has the prototype of this driver, one has Richards Moon Qlite, and one has C_K’s Ver 3.1 driver. All I have to do to compare the A17DD-S08 to the 70N03 driver is swap emitters in the proto model. (It’s got an XP-G2 where the 70N03 has an XM-L2 U3 1A)

Sounds worthwhile to me!

Ok then, tomorrow I will build a fresh new A17DD-S08 driver and a fresh new BLF17DD Ver 3.1 driver and put the same UI in each. I will then put the same XM-L2 U3 1A emitters in each M1 (from same batch and purchased together) and use the same cell for testing. In this way the test bed will be as level as I can make it. I won’t even put any of my well squeezed amperage rocks in either light. :stuck_out_tongue:

Sounds nice :slight_smile: if i ever get to the point where i have all of this figured out so i can start flashing firmwares myself, i will look forward to try it out if its ready then, Good luck

Checking the Vf of the emitters will verify the levelness of the test. Maybe also compare output at lower cell voltages.

I agree wight about not jumping the gun, just making an offer to our mega mod members who might want to eliminate this as possibility.

I built up some drivers last night, not done - not much time lately. I'll do a direct swap in the same X6 of drivers, then see (hoping this eve). I'm testing with an old XM-L2 U2 1A now to eliminate the de-domed XP-G2, so hopefully that's a better test case than the de-domed XP-G2.

Really could all be the Vf of the specific LED/MCPCB I'm seeing - dunno, but would be nice to get an understanding. In my other builds there are lots of variables - some with e-switch, some with the LED+ wire bypass of the driver (not always the best), different LED bin's/tint, etc. The only obvious thing in comparing the 3 driver designs is the original BLF v1.0 seems to have the thickest ground ring, but that's probably not exactly true - the others could have a thicker one, but not all exposed.