[released] 17mm 8x7135 with Zener & dual-PWM + stubborn: A17PZL

That is correct. Modes are working as they should - just seems to be running off of one 7135 only as it’s pulling 0.38A on the turbo mode.

I’ll be able to take some measurements with my DMM on the driver later on tonight. In the middle of this my trusty Stahl soldering iron died. Got a new iron yesterday so I’m back in business.

Ah, get it now. Wouldn’t that indicate that the single chip pwm channel was functioning normally and the multi chip channel was not? I suppose it’s possible to have bad connections on all but one chip but it seems more likely that either the other pwm pin is not connected or the firmware isn’t generating the signal on the pin. Sorry, if I’m not helping I can just butt out.

I agree, my first assumption would be that it’s a firmware problem. At a glance, the FW looks OK… but I did not scrutinize it closely.

In order for the primary channel (the 7x channel) to stop working only one 7135 needs to have it’s PWM pin shorted to GND. Then they’ll all be shorted to GND, together.

I was just staring at the render and I can see how the pwm of the 5 chips on one side connect to the single chip above the OTC but I don’t see a trace connected to the mcu. Maybe try an air wire?
-edit this is in regards to post 87 so probably not Germaine to this problem.

What board version do you have grantman321?

Yeah, that was an oops. Another thing I need to do is go through my OSH Park and clean up all old versions. I’ve just been marking them as [outdated] in order to avoid lots of dead links when people link directly to the project instead of the driver thread on here… but it’s resulted in a huge mess in my OSH Park shared projects. The driver thread for the A17-L81 is over here~~ [WIP] 17mm *9x* 7135 for dual-PWM or white/red: A17-L81

Sure looks like v013. Could it be an unplated via? I suppose a continuity test from pin 5 to one of the top side chips would tell us something. Some alcohol and a toothbrush would help too.


Please flash the current stock STAR_off_time firmware. The stock output pin is Pin6, the pin which is hooked up to 7x. That will quickly determine whether it’s a firmware issue.

I flashed the standard star_offtime originally without changing anything. It acted pretty erratically - switched modes constantly, several times per second. I figured it was because it was looking for the moon star and since that’s connected to a 7135 it was constantly changing the number of modes. But my understanding of how the firmware works is still pretty rudimentary so that could be totally wrong.

I’ve got a second driver built with the same edited star_offtime… gonna hook that up later tonight to see what it does. If it works, that’d mean there’s a hardware issue with my first driver.

It shouldn’t be looking for a solderable star on the other PWM channel… if it is, it’s a rather old version of STAR or you’ve got dual PWM disabled.

You can find the latest version at JonnyC’s site or at my code repo (linked in my sig).

ToyKeeper, that’s exactly what we are talking about. I specifically recommended that grantman321 flash with dual_pwm_start disabled in order to see what happened.

Grantman321, the initial setup phase which looks for stars only happens once each time the flashlight is turned on (eg power cycled). Once it’s up and running it does not matter what’s on that pin.

Gotcha. Well in that case I’ve definitely got something going on with the components. I flashed the newest star_offtime to it initially and it didn’t work anywhere close to right. Lemme check another driver I’ve built to see what it does. It’s also running the firmware I put up on pastebin as well.

Sounds good. If the other driver works I’d start by removing all your 7135s. One at a time if you want…

Welp driver #2 works perfectly. Low mode doesn’t even register on the DMM:

And high mode pulls between 3.00A and 3.02A:

I reckon it’s time to pull 7135s off the first one. Or maybe just salvage parts and chunk it. It’s pretty beat up.

I doubt that there’s anything really wrong with the PCB. I’d probably strip it and rebuild it, although I might throw out the 7135s. Or just check them all for shorts really quickly after I stripped it. If they don’t short then I doubt they are causing the problem.

Thank y’all so much for your help. Sorry it was somewhat of a wild goose chase. Haven’t decided yet what to do with driver #1… may end up fixing it, also might just salvage components and put them on another driver board. That one’s a little beat up and crusty with solder flux everywhere (from going in/out of brass C8 pills when testing).

Pretty psyched to have one of these working. Haven’t yet stuck it in a flashlight. Working on these has been somewhat on the back burner while I mess around with some other projects.

What LVP numbers should I be using with a 19k resistor to be somewhat conservative?

There is no need to guess about the LVP numbers. You can simply measure it. I have a firmware called battcheck which blinks out the raw ADC values, so you can just flash, measure a few voltages, plug them in to the firmware you want, then reflash.

So you can set the ADC values according to the internal voltage of a given mcu since they tend to vary 10% or more?