Open source for the shematic ? I posted the one for a prior TPS61288 version on the thread, I’ll probably post the new MP3431 version, that said do I need to use a open source license ? does it make sense to use one for hardware ? I’m a bit clueless on the subject honestly.
Made by me ? Firstly if I make drivers to sell it won’t be a lot because I’m handicapped and unfortunately my health has worsened as of late, I do the designing and modding because it’s a rewarding hobby, but making several drivers to sell is another story, plus I’m not equipped for any medium production run. So yeah, I don’t know about the price yet but it won’t be cheap.
Yes there a copper spacer, you can see it on this pic :
The Olga RS is ~3mm shorter than the reflector+centering ring, as mentionned before I planned to have it sit on the aux board (0.9mm) and so I used a 2mm spacer (plus plastic spacer on the MCPCB in the meantime), since it degrades the beam I’ll make it sit on the MCPCB an I’ll have to make a 3mm one.
For testing stuff with the 1616 I use an xplainednano board on which I replaced the 416 by a 1616, then plugged onto a breadboard (I use it as a programmer for my drivers too), there is the Xplained mini with a 817 but Anduril2 takes just a bit more than 8kB, although it can probably fit after removing some stuff like blinkies and such.
Well as I mentionned previously I mostly hacked support for the HDR (dual sense resistor), proper support would be great, we can discuss further in pm if you want ?
Ahh so it has to sit directly on the MCPCB through a big hole in the aux board (without any plastic centering ring). I’ve already ordered this 2$ TIR from kaidomain but it’s a long shot if it’ll still fit correctly without the plastic spacer… it seems to have the same dimensions as the Olga RS though…
I’m not really knowledgeable about the subject either but I think there are some fair use/”hobbyist laws” that lets us come up with designs that manufacturers can’t sue us over… I have no idea about licensing PCB designs though.
I’m sorry, I shouldn’t casually ask side questions without thinking about them first… I meant to ask how much would this cost someone to order the pcb and parts (sample PCBs are often sold as a batch (JLCPCB sells 5 boards for 10:money_mouth_face:). By “open source” I just meant to ask if you had the shared the cad files (KiCad??). I’m also wondering if maybe paying for smd assembly of common components (jelly bean) on one side of the board can be worth it… as I don’t have any smt resistors and capacitors in various sizes at home.
I realize this is a bigger question than what I meant to ask and I still haven’t finished reading the whole thread (very informative, and it’s impressive to see you discuss optimal component values).
I’m wishing you the best thefreeman (mes meilleurs voeux).
I’ll share oshpark projects and a mouser cart like I did here for linear drivers for those who wants to make it themselves.
The boards are not very costly, 3.7$ for three 22mm boards, for JLCPCB I’ll need to re check but I think I would have to enlarge some vias to use the default (cheap) capabilities.
I’ll have to run the total for the parts, it’s the same as the linear drivers but without the linear FET and + the MP3431,XAL7030/7070, and 1206 caps.
Ideally I’d like to do a final version before sharing it without the hardware delay (4 components) for the HDR FET (when full anduril support) and with a few minor layout changes.
Although I’m not sure what host to use it in, it seems like lot of side switch 14500 lights have the switch mounted on the board, which isn’t very problematic, just need a different layout, some have 2 PCBs like the Sofirn SP10S, that’s a bit more annoying, plus the SP10S is too big for a 14500 light in my opinion.
I’m interested if you know of small 14500 hosts that would be suitable.
There is the FWAA, adapting to it is easy (just add a switch ring), although I prefer a single emitter version, which apparently is in the work.
I wish Hank would make a small 14500 light, and a small 18650 single emitter one too.
Sure, this is fine with me, or here is ok. I may also have to consult ToyKeeper for advice so I hope she will be ok with that.
Regarding boards, I think most non-hardware people aren’t really equipped to assemble their own drivers from a blank board, given the need for SMT soldering and rework tools, and the need to possibly get parts from multiple sources. As a software person without a proper electronics lab, I hate working on hardware because I too often find I need a 5 cent resistor for something, and I have to order it online instead of pulling it out of a parts drawer. Then after it arrives and I install it, I find I have to order another one. So it would be great to have assembled boards available.
Do you think it might be possible to use Seeedstudio or someplace similar to manufacture boards? I’d be happy to buy some boards. I’d like for us to become more independent from flashlight manufacturers for this stuff.
So I’m in the process of converting my drivers to use the DAC instead of PWM, there was two reasons I was on the fence about the DAC :
the lower resolution of 8bits, which would make the bottom of the ramp quite coarse and decrease the dimming range, even with 2 sense resistors (HDR) the minimum for a 5A 6V driver would be 77uA 6V, my goal has always been at least 100uA 3V (ZL H600 II) so that’s not enough, but if Gchart succeeds to implement dynamic VREF then there will be enough resolution.
the main point about using the DAC is to not have to use the LDO and a bunch of passives that comes with it and PWM (input C for LDO, VBATT divider, PWM RC filter), but I need a constant voltage to drive the HDR FET that switches between the two sense resistors, since the Rdson of this FET is part of the total Rsense it has to remain constant through the whole battery range (4.2 to 2.8V). Except that was with the previous FET, the new one I use has a very flat RDSON/VGS curve according to the datasheet, so I measured it to be sure :
Only about +0.25mΩ from 4.2 to 2.8V, which for example on a total Rsense of 8mΩ means only –3% output current at 2.8V vs 4.2V, which is… completely fine!
Additionally the DAC is faster than filtered PWM, which is good for fast strobe modes, it produces no ripple, and shouldn’t make a flash when ramping up, so no delay needed on HDR FET turn on.
Conclusion : let’s remove the LDO and 5 passives.
Thanks to the lower component count the BCK18_HDR (18mm clearance) driver can be one sided.
You should see how I’m equipped :disappointed: I think many modders here have better equipments than me.
For reflowing I do it on a ”hotplate” which is just a small sheet of copper heated by my soldering iron. For the second side or for rework I preheat the board on the hotplate (with a spacer) and heat the top of the board with an infrared heating tool I made from a car cigar lighter…
For applying the paste, because I prototype a lot buying stencils each time would cost quite bit, so I use one only for the T1616, I do the rest manually with this dispenser which main advantage is to dispense precisely with one hand, same precision can be achieve with two hands and a 1ml syringe with 25G tip. But once I’ll have more final versions I’ll use stencils because it is so much faster and easier.
And then a small 10x loupe for inspection, but that’s it mostly, a bit primitive but it works.
About parts, well I built an inventory because I prototype, but once you have a BOM that’s not a problem.
Though I understand that people would prefer to buy already made drivers, I looked very briefly at PCB assembly services before but I haven’t done a simulation or something like that, what I remember seeing here is a GXB172 driver group buy that never went through due to not enough quantity to be viable. One problem is also the many different sizes.
About the Dx series, I skimmed through it when you posted it on Gchart’s thread, but I don’t know what is really good for us there, the bigger DB ones have internal Op Amps, but with 8mV max V offset they are not suited for our application. Still only one DAC output so we can’t use it for dual channel drivers, but it’s 10bit so thats better than 1 series, DU has native USB but unfortunately sacrifices the DAC for it.
Wow it’s great to scroll through and see your iterations. That last one looks like it has few enough components to be able to be fit into a FWAA sized board!
Digikey should receive 30000 1616 this month, last month they got 6000 and they were gone in 3 days lol.
Yeah according to your measurement it needs 16.5mm on top and 14 on the bottom, so I’ll try to do a 14mm clearance one with the DAC, then just add the switch ring to it.
Yeah, drivers are rough. Grab a random light off the shelf and decide I want a different firmware on it?
Gotta find out if there even is an available driver in the right size, for the right voltage input/output. Is it from somebody that uses Anduril or ATTinys already? Which ATTiny and do I have the means to flash it, or do I need to figure that out too? Check the BOM for the driver, order from OSHPark. Wait. Then I have to schedule a full evening to build and program the driver, and test it before assembling the light…
Hot plate, hot air, soldering iron, test-LED bed, bench power supply. Solder, solder paste, flux, wires, test leads, magnification of some sort usually, multimeter, a bunch of different tweezers…
I have so many lights that I just don’t reach for on a daily basis simply because of the UI. And it’s so hard on the creators’ side too, like you’d have to make and upload so many versions of each driver in applicable sizes.
How do you see when digikey is getting stuff and the quantity they’re getting? Mouser has that info right on the page but I couldn’t find it anywhere on digikey.
I just ordered parts and PCBs for one of the DAC-controlled layouts. Now for the wait before everything arrives… should give me time to get the firmware ready!
We’re talking about the attiny’s internal DAC, using that to control current instead of using PWM. Not an external DAC. So I guess maybe you could say that this is “proper code for attiny”.
And as you’re probably trying to bring up again… yes, YLP has created a control mechanism within the attiny to control a FET linearly instead of relying on an op-amp. In reading some of the posts they’ve made of their control scheme, yes, it actually does sound difficult and involved. Certainly not impossible though. So I invite you, if you feel that it should not be so difficult, would you like to go ahead and make that and share it with the rest of us?
Some of that control mechanism might actually be easier to write (and faster to execute) with the newer attiny’s with the use of Core Independent Peripherals and the Event System. Basically you could have the input (reading of Vsense) trigger updates to the output control (DAC or PWM) without relying on CPU cycles.
