Oshpark Projects

Fair enough. Unfortunately… I don’t understand my position that well myself. As you know, my understanding is that we want to put capacitance very close to sensitive but low-draw devices. The idea, as I understand it, is that in the event of a “problem” in the power supply the PCB traces provide enough resistance and/or inductance to allow the cap to smooth power for the nearby device “before” other factors can affect the cap.

If I’m way off base I hope some of our more knowledgeable folks will swoop in and point us to good explanations!

A lot of what you guys write I just get the gist of but don’t fully comprehend. Is it possible to run the traces differently on the 17mm drivers so that a momentary switch can be used on the tail of a flashlight and not run a lead or wire alongside the battery? I would like the ability to use a momentary switch on the tail of a light using the FET, Star OS without making a jumper to the switch. In my imagination it’s possible but I lack the knowledge or skills to imagine how or write it out for Oshpark. Before I get too into this, is this possible to do?

Well with the Small Sun ZY-A629, the driver plate at the front of the flashlight (where our drivers currently sit) is a simple contact plate with a resistor bridge to ground, the actual driver that controls the flashies and stuff are on the clicky end. It would be possible to design the clicky end to be the “driver” by having the electronics be on that end, but the architecture (space for batteries/springs) would be incredibly difficult from flashlight to flashlight.

Imagine a C8 (or many of our favorite lights) that was end cap driver driven

Sorry for the derail

For that hardware/firmware, you just have to ground pin 2 to control it. The switch can even be on a remote 2-wire cable. On some it would be easier than others (ZY-T08, with batteries side by side, leaves space for a wire down the middle). Doing it in a way that the tube can still unscrew from the head without messing up the switch connection is the part where it gets not so straightforward.

I know this has been covered but there are currently several different threads on the subject and its almost impossible to find info, as is with the new design with the CAP on Batt+ to GND and no gate resistor does the AOD510 FET work properly?

What is the [what looks like an 0805 pad] marked 4 connected to MCU pin2?

Also on this board where would the zener diode go?

This is like quantum mechanics, the more I learn the less I know. :nerd_face: My goal is to plug it all together in something like a convoy S2 or Sinner’s copper 18350 host. How thin could the wires safely be? They don’t carry the full amps that the light will be using if I understand correctly. Then if I run a wire to the switch through the body, how do I change the battery of a single cell light without having to remove the wire?

I guess we need Matt to have success with his little switch. That would probably be the easiest. (For me)

Yep, those are the obstacles you'll have to figure out and the solution will be different for different lights. And on some it may well turn out to not be possible (or practical).

Resistor at pin 2 is for the off-time 1uF/10v capacitor. Zener diode would go anywhere on the trace from the D1 pad (resistor instead of diode, on a zener-mod driver) and MCU pin 8. Most convenient would probably be to put it between one of the vias and to ground.

This should be no problem.

I see what you are talking about - the old version numbering definitely went pear-shaped. We had these things:

  1. Original Gangsta
  2. v2 / Rev 2 / V2.0 / etc?
  3. V3.0 (BLF15DD V3.0 )

All of the old boards had the same silkscreen info between versions (such as “BLF17DD” for example). I see that the silkscreen has been updated to include the V1.0 on the latest boards. For telling physical boards apart this functions, but for discussion on the forum it seems that we still have a nomenclature problem, depending on how you plan to increment that number and how many iterations we have. I assume that you plan to iterate by 0.1 (so the next version is V1.1). As long as there aren’t more than 9 more revisions it shouldn’t be an issue. I’d have gone with a different, zero-overlap, scheme such as as starting at “r100”.

Very, very thin. If you were determined to make this happen in a regular host, I can only think of one solid way to make it work. Choose an oversize host (Solarforce L2i springs to mind, or any 26650 host) and run it on an 18650, two 18350’s, whatever. Now you need a battery sleeve setup with two coaxial rings on it, to carry the signal from the switch PCB to the driver. (probably easiest to do this with two copper sheets rolled into concentric cylinders with an insulator on the inside, the between side, and the outside) The special driver will have (semi eliptic?) springs to contact the coaxial rings, so will the switch PCB or a contact board attached to the switch PCB. Remember that you’ll also need to get the battery shorted to GND. This is all doable, but I’d say neither you nor I really want to go through all the work.

Yes, AOD510 works with no gate resistor after relocating the cap.

You are thinking of MCU pin 7 (aka PB2).

Cereal_killer is asking about PB3 (MCU pin 2). The pad is a 0805 and it’s there for the offtime cap. When used with the ontime firmware this is also called “Star 4”.
EDIT: Clearly that’s exactly what comfychair said. I was confused about what he said, even though he said it quite plainly. He was correct and I just repeated what he said!

Huh? That's what I said... let me try it this way.

Resistor at pin 2 is for the off-time 1uF/10v capacitor.

Zener diode would go anywhere on the trace from the D1 pad (resistor instead of diode, on a zener-mod driver) and MCU pin 8. Most convenient would probably be to put it between one of the vias and to ground.

My mistake comfychair! You can’t correct someone who’s already right! You said it right, I read what you said wrong. I’ve really gotta slow down.

Ah should’a figured that one, I’m literally right in the middle of learning eagle (since this time yesterday) so my brain is pretty taxed right now, thanks guys.

If you're using firmware other than the STAR off-time you can use the pads as jumpers (same thing, they're just bigger)... or as the switch connection for the momentary version.

(I did call it 'resistor' when referencing the pads, that's probably what did it) :)

BLF15DD Version 1.0: https://oshpark.com/shared_projects/V4ua4iuK

I have removed ALL the old Direct Driver 15/17/20 drivers. I didn't even realize that I had been leaving old versions up. The only boards you will be able to get your hands on are the DD, DD-Z, and linear version 1.0 boards now.

Hey guys any of you US folks interested in getting in on a larger digikey order? I need to reup my own supply, I’m looking at ordering a few hundred resistors, 50 input cap’s and some 13A’s and AOD510’s, I’m probably going to place my order tomorrow, if anyone is interested in getting any of the standard 105c parts and/or FET’s please let me know ASAP and we can get it setup to get better prices.

Also getting some neutral XP-E2’s but the first level price break doesnt start till 50pcs (but still only $2.57/pc)

What resistors are you buying?