[WIP] 17mm DD+single-7135 driver / single sided / Dual-PWM

Sorry, been way behind on this, so just ordered my first set of v032 boards. I took a close look at MCU pin#3 and looks like it’s connected to a pad covered over by the solder mask, but that’s fine - easy enough to scrape off, and I no longer would have to solder a wire direct to the MCU pin.

Somewhere above it was mentioned to use R1/R2 as 10x the values — this would be great to cut down parasitic drain, which is a problem I’m trying to address. How would this work exactly in the voltage divider, and the values to use in the firmware? Anyone try this or should it work ok?

Depends a lot on the type of circuit breaker or fuse. Some large 15A breakers will easily supply 20-25A forever. The slimmer type, especially if next to another loaded circuit, may not fare as well. I used to have a microwave pulling 19A (official rating was 1500W…) on a 15A circuit together with about 2-3A of lighting. The lights would dim when using the microwave… but the breaker never tripped. The only sure way to find out is to try it.

Pro Tip: You want those breakers to trip. It’s what they were designed for. If they aren’t tripping on overcurrent, they’re not doing their job and are very dangerous! :open_mouth: Worse, the issue might not be the breaker itself, but the wiring. It could be already damaging your electronics. Sorry to be so alarmist, but as an electrician, I’m trained to care about these things.

I decided to give the large heat gun that’s been lying around my job (for a few decades) a try. I think it’s great for emitters but it doesn’t give me much/enough control on driver boards. I wanted to touch up some resistors on the edge of the board but I couldn’t avoid desoldering the MPU and 7135 at the same time. The FET wasn’t affected — it was far enough away. If I can’t fashion a nozzle for it I’ll gladly likely spring for the 858D. Now that I think about it, the air flow with a nozzle on that gun would be far too high… Parts would be flying everywhere. A purpose built hot air station would be worth a few bucks.

FWIW, after watching the technique shown at the 1:40 mark in this video I’ve been pretty happy with most surface mount work using an iron. However the pads on some of our drivers are so small it’s a bit more difficult.

No worries, said microwave is now on its own 20A circuit. I was just pointing out that 15A is not a hard limit. Few breakers will trip right at 15A and properly installed wiring won’t magically burn up at 16A. But you certainly already know that :slight_smile: In fact, the only wiring I’ve hard melt down on me was crappy aluminium (probably on the wrong type of socket) in an apartment building from the 70s. It was only lightly loaded.

Hello everyone .
After making some wight’s 17mm fet drivers (A17DD) , i think i should step to this driver now .
So , first question : Which package of attiny is compatible with these drivers (if i want to use attiny 25/85) . SSU ? or what ?

Also , which version of the board i should use and which is the preffered components list ?

thanksss

The parts list is the same as the A17DD, with the addition of a 7135 chip.

If you are using in an e-switch light, you may want to substitute the resistors with 10x higher values, as has been recently discussed, to lower the parasitic drain when not in use.

I’m using v009, not sure on the differences of the later revisions.

Thank you FmC !
Any clue about which version of the board i should use ? I’m not interested in e-switch.
Also which package of attiny i should use . On A17DD i used attiny13a-SSU . So in attiny 25/85 still SSU is what i need ?

Attiny25v-SSU would be the right size. the 85 doesn’t come in SSU package so you would have to use the SU package and bend the legs under, but it’s workable.

I’m not current on the different board versions though

Whether you use the 13A or 25 will depend on which firmware you wish to utilize. The A6 firmware uses the 13A, Bistro uses the 25.

V013 is probably the board to use.

I know about the firmwares for each attiny .
i will build some with 13a and some with 25 .

Thank you Dale ! :beer:

Built today 4 drivers :
One with attiny25 , and it works like a one mode driver (like the led minus and the ground is connected)…
Three with attiny13a that don’t even light up…

Checked all 4 boards for shorts (if there was any drop of solder for example) , but there aren’t any.

Any clue ? I believe there is a short inside the pcb layer , but i don’t know….

Can’t you use a DMM for shortcut measurement? With so few parts it should be easy to find.

On the attiny25 board there is a short between led minus and ground …
Desoldered all the components and it’s still the same . Soldered components in an other board and works perfect .

On the other 3 boards , checked the diode (if it was the other way around) but it is the right way installed .

Did you put the ATTiny on in proper orientation? Don’t laugh, I’ve put em on backwards before…

Edit: I’ve also built a light completely that wouldn’t work at all, only to find the MCU was never flashed with firmware.

Pictures, show us the drivers…

The orientation is right , checked that too .
I flashed the attinys as long as i received them , but i’m going to reflash them today afternoon.

[quote=wight]
Up front: Sorry if I miss anything folks - I don’t have a lot of time so I’ve skimmed the last 10+ posts.

Do any BLF member experiment to confirm these components values (resistors and capacitors)? Wight is offline for some time now. Perhaps he had made the research to find out. Thanks if someone can help. Already ordered the necessary stuff to start building some V032 boards.

Mozart - not sure what parts you are referring to exactly for confirming. I lost track of all this - I'm using MtnE's MTN17DDm v1.1 boards now, mostly. I dunno for what MCU or usage you are building it for. For 13A's, it's all the standard parts for C1, D1, R1, R2, and OTC.

Tom E, thanks for your reply.
I need to build some drivers for 1s flashlights with single, triple and quad emitters. I will be using 13A and 25 tinys. The parts that I would like to confirm are for the 25s. Can I use 1uf for C1, or a larger value is recomended? I have some 0603 4.7uf X7R capacitors if needed for C1. The otc can be 10uf with 100k pulldown resistor R5? As I will use these drivers with one cell lights the zener load resistor R3 can be 200ohm or a smaller value one? For the R6 FET gate pulldown I’m thinking to try 40k to 60k as Richard use in his 1.11 v driver, what do you think? Please, I need some “light guru” advice to correctly build these drivers.