I'm sure there's history on this, but does the AOD510 MOSFET perform as well as the Vishay 70N02?
We might need to get some current numbers to find out for sure but it may do even better. On state resistance is hard to compare between fets since they are often spec’d at different gate voltages and aren’t exactly the same from one FET to the next.
I don't have a current measurement, but I have checked voltage drop across both in a like-for-like setup. 70N02 = 32.6mV, AOD510 = 41.5mV. Higher voltage drop means higher resistance. So they're not equal, but the AOD510 is readily available and relatively affordable and they're only 'not as good' when compared to a really excellent one.
And you can buy it 
(that’s always a plus!)
Comfy what are you using for the + button on that driver there? Very clean install (as usual). Also very good news about the 510’s! I was really getting worried as I’d been testing different gate resistor values (I have every resistor pack coming from fasttech so I wasn’t gonna give up yet but I tested every value resistor I had in the spare resistor tube and nothing had worked yet so that’s great to see). Thank you for your time/money.
Side note my 858D will be here Tuesday!
Just a piece of scrap sheet copper, I think it's around .040" thick. Not much room in that little Z1...
Revision revised again (probably won't be the last time, either)!
dave_ suggested an alternate fix in the 'scope images' thread (post #50, in case the pagenumber thing breaks the link for you). Instead of adding a second capacitor in parallel with the diode (which does work acceptably well), just relocate the one original cap from its original spot between the diode output and ground, to just plain between B+ and ground.
This is the extra-cap version:
Gives waveforms that look like this:
Acceptable, and it makes the driver reliable with the gate resistor deleted. But requires an extra capacitor.
dave_'s suggestion:
Gives you this:
Waveforms look better, needs fewer parts, and works just as well.
The capacitor can go anywhere on the board where it can connect between B+ and ground. There are many options on top or bottom of the board that will give the same connections. On the topside, there's a single ground via right beside the four B+ vias at the LED+ wire pad, if you'd prefer that it not be on the spring side of the board.
A larger value capacitor will flatten the oscillation more than shown above, but this works well enough and the part is the same as what comes on the Nanjg boards, for those who are using that as a source instead of buying bare parts in bulk. For those wanting to get more involved, you can change to a larger value cap if you wish. Experimentation required, and probably needs to be verified with your own scope images if you want to try something different.
ANOTHER SET of shared carts - same components as before, just with 1 cap per driver instead of 2:
shared cart- BLF-SRKDD | Digi-Key
I hope you dont mind me posting this here but I got my first Osh Park shipment today. I just need to know now how it all goes together. 
Uh-oh! Those spacer boards seem to be missing the center hole?!?
Is there a way to order different boards with the same order? I just ordered some things and I had to pay two times…I hope they will send it together.
+1, had to do that myself and the two sets were fabbed a week apart and shipped separately. They might do overseas differently as Steve just posted an order with several boards that came together.
I did three orders right after each other, three separate pay sessions, but they arrived in the same envelope. Apparently the Oshpark software has an efficiency thingy build in, or even perhaps there are real humans involved there somewhere :-)
I thought I did something wrong, I would definitely feel bad if they would send a 1$ order separately.
I used the little FET Scott sent me with the then new BLFTiny10 and put it in my Texas Poker, running a bit over 3A from an Efest IMR10440 to a de-domed XP-G2 R5 1A. None of the extra resistors or such was known at the time. I don’t have moon engaged, just running 4 modes. And it works fine. So far. I use it pretty often and in various modes, but usually set it to come on in the lowest mode before shutting it down. After I built it, the issues came into light of the possible mode changing failures. I had considered opening it back up to engage moon mode, but feared it would bring this issue to my driver.
Should I worry about an issue arising? This is an expensive light, one of a kind, and I don’t relish making changes unnecessarily. If something get’s damaged it might not be possible to replace or at the very least will be expensive to do so. With it in working order, should I worry about it?
Pretty sure I’d never go this route again, having the full custom Ti light made turned into quite a more costly venture than expected. With the cost of an Olight SR90 AND Fenix TK61 combined rolled into this 3” Ti light, I’m not eager to make changes to it that don’t need to be made, ya know? I’ve already been into it 4 times with driver changes and one emitter change. As most of y’all know, the more you work on one the easier it is to kill reliability. I initially had requested a second pill, forseeing this potential even a year ago. But, alas, I only have the working light with no spares.
Agreed if OSHPark had an “add to cart” deal and you could order multiple boards that would be excellent for sure
Remember its a tiny company. I think it has to do with how they process them once the panels come back from fab, I imagine it can be pretty confusing breaking all the boards apart and packaging them up so if they’ve got a system that works I dont think they need to change it.
I’ve personally placed over 3 dozen orders for over 120 boards and never once had an issue, they’ve got their system down pretty well, other than the strange way you check out for each set of boards at a time it’s a pretty hassle free system they’re running. I’ve said this before but cudos to Lean and the rest of the OSHPark team, they enable so much of what we do here, this flashlight hobby of ours would be a lot more expensive if it wernt for them.
I think it's almost certain that any board that has re-used the Nanjg's original diode/capacitor layout in the power supply to the MCU suffers from the same overvoltage thing shown in my scope images. Even an original 105C does it, though when driving 7135s it doesn't rise to the level that causes odd behavior.
Move the capacitor at C1. Originally it goes between the diode's output and ground. The boosting goes away if it's moved to between B+ and ground, and then gate/pulldown resistors are no longer needed. In existing designs replace the gate resistor with a jumper. In new designs their pads can be eliminated entirely, freeing up valuable space.
Is there a guide anywhere for designing these things? Is there anything that will let you edit the design files from Oshpark?
Design? No. Layout? Yes. Matthaus posted a thread on layout using Eagle. Learning Eagle is definitely a both-feet-first endeavor.
Editing what’s on Oshpark? Mostly no. Many/most people upload only “gerber” format output files to Oshpark. In an EDA suite such as Eagle you work with it’s native format and then output gerbers as the finished, mostly uneditable product. Think of it as writing a document in MS Word and then printing it to an Adobe Acrobat file. Very similar end result here - while you can mess around with a Gerber, it’s about as effective as trying to make changes to a complex document that’s already been committed to a PDF.
Mattaus and WarHawk-AVG both have the BLF20DD Eagle files IIRC. I believe it was Mattaus’s intention to keep the circulation of the Eagle BRD/SCH files down in order to prevent a flood of minor variants confusing people (or worse, a flood of non-functional variants confusing people). I’m sure one of them can hook you up!
I've been out of the loop but if anyone wants changes made just let me know. The only thing I ask is that we keep the changes to single revisions and preferably single versions of a particular size. I don't want to have to manage 5 (bum plucked number) different versions of the 17DD just so that we can have one with a resistor, one without, one with a slightly different layout, one with extra caps, one with a FET, one with AMC chips, and so on.
I'm pretty bad at revision management as it is, going crazy is a recipe for disaster. The ultimate goal here is ONE perfect DD board.
I’m up for it Mattaus if you want to send me the brd and sch files….I can tweak what you have and then send em back to you to post to OSHPark…this way the revision stays sane