Oshpark Projects

I'll review the 70N05 boards tonight and see if anything sticks out as to why the 17DD is being such a PITA. I'm guessing no one has tried the 20DD yet?

I'll also make the others changes Comfy mentioned.

WarHawk, I had 2 star engaged to the PWM leg, grounding out the PWM. Once that jumper was fully removed it worked again.

BUT, I soldered leg 5 to ground and had the same 4 modes, moon wasn’t engaged by doing that. So I don’t know what’s going on there. Took that off and it’s still working fine in 4 modes.

Here’s some numbers for the crunchers out there. This test emitter is, I believe, an XM-L2 T6 3C on a 16mm Noctigon glued to a 1/2” thick copper insert in the HD2010 Aluminum pill. Wired directly to the star and run with my DMM using it’s 6” long 12ga leads with gold plated banana plugs…

Lo to High with rested cells

Samsung 25R @ 4.13V 2500mAh
.02, .43, 2.37, 5.26A

Sony C4 @ 4.16V 2600mAh
.03, .46, 2.45, 5.44A

Efest 35A @ 4.20V 2600mAh?
.03, .46, 2.49, 5.60A

Samsung 20R @ 4.20V 2000mAh
.03, .48, 2.60, 5.70A

Sony C5 @ 4.15V 2600mAh
.03, .46, 2.50, 5.44A

Test cell @ 4.20V 1500mAh
.03, .48, 2.55, 5.69A

So it’s consistent pretty much across the board, with the top performing cells showing their customary margin of lead. I’m charging those cells that were not fully charged, but I expect they’ll be consistent with the others. I don’t know why this FET driver is showing lesser numbers than I’ve gotten previously unless it’s the T6 itself.

Previous tests were also with a single XML2 on copper?

Looking at the FET 15 if the Attiny were shifted to the left then C1 R1, R2, and two extra FET gate R’s could be lined up(rotate C1 90 degrees and put the 3R’s parallel to it below) one below the other. This would also allow LED+ to be nudged left and be diametrically opposite LED-. This would put pins 2&3 closer to the ground ring for star connection.

EDIT - Just a suggestion but you might hold off on reworking the 15 until we find out what the limit is on that FET. The K4212 looks very robust and has an extremely low Rds of ~ 3mOhms at 4.5V and is 3.4mm x 3.4mm if we need to change that and might work for the 17mm board.

Digikey page a bunch of options.

That was with the same emitter set-up but no driver, straight direct drive. In that instance I was seeing High at 6.85-7.18A.

With the Qlite modded FET driver I was seeing 5.87-6.30A from these same cells. So it looks as though the BLF FET board might be running a bit lower than the Qlite FET board.

Edit: Just found notes where my C8 with the big copper pill from Buck and a modified Qlite FET driver pulled 6.66A from a 20R in a built light. Same light with an Efest 35A makes 6.61A and 1673 OTF at start-up, 1497 OTF at 30 seconds. This with an XM-L2 U2 1A.

You have the two new resistors on this one, right? Try jumping from B+ (or LED+, same thing) to the gate on the FET, see if it goes up when you do that. Also try jumping across just the resistor inline with the gate.

If it shows a big jump with the resistor bypassed it means the gate isn't opening fully when going through the resistor, we may need to look for a different FET that doesn't need the stupid resistors. I have a few of the 2SK4212s I can try, they have a lower gate charge spec.

Running the 18500 for ease of handling, I was seeing just over 4A on high with zero change both visibly and on the meter when I crossed the positive to the gate. Showing 2.7A on Med/Hi it did indeed jump in brightness and to 4A on the DMM.

Not sure about crossing or bridging the resistor, didn’t see any change there either.

Edit: Trying again to jump the resistor I touched the wrong things and it popped and smoked. I think it’s staying dead this time. I gave it a standing 10 count and they carried it off on a stretcher. It doesn’t look good.

No, wrong K4212. It's from NEC/Renesas, 2SK4212A. About double the Rds(on), but much lower gate charge. TO-252/DPAK package. The one that comes on the red 'JB-2013-11' driver. That exact part is discontinued/EOL, and the replacement sucks balls, specs nowhere near compatible for this low-voltage-overhead setup. The replacement would probably work fine in a different circuit. The old 2SK4212s are available in bulk still, but only as surplus NOS and only from possibly questionable vendors on aliexpress.

This one looks kinda interesting as a possible substitute: http://www.digikey.com/product-detail/en/AOD510/785-1481-1-ND/3603497

A little bit lower Rds(on), and Qg is much lower and closer to the 2SK4212 that started this whole mess in the first place.

Hey man, you know what they say: you can't make a driver without breaking a few omelettes... er, no wait...

Lol, and yes I agree.

Just went out to take the trash down to the road. Carried the C8, M8 and L2P with me. None are throwers. All are FET modded. And wouldn’t you know I saw a couple of critters out at 100 yds that I just couldn’t quite identify even with the big M8, granted by the time I pulled it out they had moved off and were closer to 200 yds away. Might have been a pair of foxes but I haven’t seen foxes around here in a very long time. Nearly 30 years. About the size of a big housecat but with large puffy tails. Had to’ve been foxes. Cats tend to slink away, these did a sort of bobbing lope. Almost took my camera, wouldn’t you know I didn’t! lol

At any rate, the L2P Triple worked quite nicely, very good for a walking light with it’s wider illumination pattern from the 10507. I didn’t use Turbo very much, but purposely ran it on High for several minutes and it was really too bright. The 2nd level, Med, is about right for walking. It shifted levels reliably, never flickered, and all the dust didn’t show any PWM in any mode.

I lit up a Jack Rabbit with the C8 from about 40 yds and he got confused. He came towards the light, unafraid, stopping to nibble a couple of times, but got within about 10 yds of me before I said something to him and he loped off. Still not afraid but putting some distance between himself and this unfamiliar small sun.

The big M8 with it’s MT-G2 can really light up a tree! For anyone checking into a tree at night it makes a 40’ tall tree seem to be in daylight. We’ve lost a couple of trees looks like. Early bloomers and a late freeze caught em. Here we are sitting at 70º at 10 O’clock at night. Walnut tree’s are blooming out, grass is growing (gonna have to mow in the next few days)

Nice night. :slight_smile:

I’m looking for something smaller than the dpac for the 17 mm board so there’s room for extra components. There was an entire page of K4212 in stock at digikey. Are they all the wrong ones?

It's not a type, it's NEC's model number for that specific part. What did you search for to get that list? I don't see anything there that looks related.

http://www.digikey.com/product-search/en?vendor=0&keywords=2sk4212

http://www.aliexpress.com/w/wholesale-2sk4212.html

It was the package LFPAK33. Less than 4mm square with low Rds at 4.5V and very high power dissipation.
EDIT- I realize This is the usual pap but it still seems worth a look.

WOW! Interesting and if those specs on the RDS (on) then wow…very low resistance…nice

The current and power ratings are through the roof as well. I think I looked at ones like these in the thread where CC and Werner were working on this idea. They’re not expensive and have been proven up to 175C. Less than half the size of the TO 252 leaves room on the 17mm board for needed resistors. Pick some up?

EDIT- The LFPAK 56 is 5x6 mm(slightly larger than a 7135 including pins) the LFPAK 33 is 3x3 mm(smaller than a 7135). The 56 has even lower Rds on and higher power dissipation than the 33.

Depending on the Qg, it probably won't need the resistors. And if you're picking a new part might as well make sure to get one that works with the simplest circuit possible, i.e., no resistors.

Or, try the AOD510 on the existing board design, it may not need the resistors either. There's not going to be much measurable difference between 4mOhms and 2mOhms, there's no magic bullet there, it's still limited to no more than what it would do with the cell wired direct to the LEDs.

What did you search for to get that list?
I remember the FET led4power is using on his driver had this odd shape and very high power dissipation numbers and the K4212 from earlier posts and just spent the evening wandering the web looking at specs. When I googled k4212 the Digikey link came up and I looked at pictures until I saw this odd shape again. Googled some more and found the NXP page and mouser links. BTW mouser is soo much easier to navigate for parts.

True, but the smaller package should work with either the 17 or 15mm boards and might eliminate parts/traces on the backside. They also have higher operating temps and higher current ratings for their size which may or may not be helpful. It’s a newer, possibly better design than the Dpak. I’m still going to try out the 2502 but it’s not as likely to be able to handle an imr 14500 or 14650. In the end, whatever fits and works is fine by me but we’re still in development so I don’t see any particular reason to be wedded to an older part unless it works better. The “33” is the same size as the 2502 but is more than an order of magnitude more robust in almost every respect and the “56” is only slightly larger and even more potent. There may well be reasons that they won’t work but it may also be true that they’ll work better.

I have 150 of the Vishay 70N02s, that's one reason to use them... :Sp

any reason to use the luxdrv when STAR V1.1 and Star_mon V1.0 work…or does it not work…I haven’t gotten my boards to build yet