And I’m using the Kester 66 “44” solder paste.
Edit: Ooops! That’s my solder wire, I’m using Kester EP256 solder paste in a syringe. It doesn’t specify any more than that on the syringe, can’t remember which variant it is. (63/37 I believe, with no clean flux)
Thanks for doing all this Dale. A continuity check is a royal tedious pita but will reveal cold joints like that. You just have to make sure the probe is on the pin and not the pad and sometimes probe pressure can create a connection that doesn’t exist with pressure removed. I’ve had emitters that looked fine but had the same problem so a visual inspection won’t reveal everything.
No clean just means that the residue doesn’t need to be removed but it’s still there.
Good work! Thanks for testing with the PF cells. Did you happen to take any readings that showed the increasing output thing again?
Can you flash a STAR firmware build with a lower freq PWM? HarleyQuin posted a little chart with a writeup on what does what. I’m pretty sure that all you’d need to do to drop from 19kHz to 2.4kHz is set your low fuse to 0×65. CPU freq would not change, only the divider.
I cleaned it with a cotton t-shirt and a toothpick to get into the small crevices, best I could. Oh well. Time spent por nada.
Actually, upon re-reading Mattaus’s post on the issue and glancing at the datasheet, I doubt that flashing with a lower freq PWM is going to do much. Shouldn’t hurt anything of course. High frequency PWM should just limit how low the PWM’d output actually gets. My bad!
I’m using the STAR firmware that I use for the FET driver builds.
I would like to develop your level of patience. Your attention to detail is helpful and I am learning second hand from your pictures and explanations. Thank you for that.
about ready to send it/them on that blind date with the 16lb sledge.
Sorry, I didn’t mean to imply that you didn’t, only that “no clean” doesn’t mean “clean” but “no need to clean”.
Dale, I feel that a 16lb sledge while effective, it lacks character. If it must be put down, I propose that as it has received so much attention and care during its life that it’s demise should be equal. As someone so skilled with a camera perhaps a series of high speed photos to document it being rendered asunder by a precise and carefully applied pyrotechnic charge. J)
I’d have my cop neighbor shoot it with a .50 BMG but I don’t have all year waiting for him to zero in…
Hmm, 16lb sledge. While I sympathize with the plight of the crash test dummy, it is their preordained lot in life to suffer for the benefit of others. Not alone in this, others throughout history have paid the ultimate price, sometimes merely for entertainment. Some of you may remember Wile E. Coyote, Super Dave Osborne, and who could forget “Oh No, Mr Bill!” Whomp! 16lb sledge meets playdoh.
However, the cost of the parts that went into this Wile D. Bill driver is not insignificant so I ask you Mr Hands, is it worth it?
Has it been tested in single mode for stability?
any components overheating?
Dale, you really ought to get some extra flux, it makes working with these smaller components a lot easier. I use the MG Chemicals 835 Rosin Flux (non-corrosive, non conductive) liberally on most projects working with smaller parts. It makes a sticky mess but it works well and comes off easily with non-chlorinated brake cleaner (wear gloves, spray outside!) A $8 bottle will last for years and years.
Of course you don't need extra flux for everything, that's definitely not true, but when you're working with smaller packages it allows you to drag solder and use other techniques that are a bit faster and give a cleaner result in the end. Lots of flux is key to easily hand soldering surface mount components.
This dude's video is pretty fun to watch (crank up your speakers!)
It is interesting that the middle modes don't work. I guess we'll have to figure out what PWM frequency this chip likes best, if you're running the phase correct right now and it doesn't like it I guess you could try the fast PWM (switch 0x21 to 0x23) and try that. If that doesn't work, we could try halving the frequency and going back to phase correct. I guess what we have to figure out is how the buck IC responds to different signals. Just like the FETs (and each of those is different) is different than the 7135s, the buck IC also probably has its own set of preferences. 
I wonder what is the pulse frequency of the buck converter? Would the PWM possibly harmonic with that frequency in the middle modes?
In this post Matt talks about pwm frequency and low modes.
Thanks for linking that post. I guess what also remains to be seen is how the output from the buck IC correlates with the PWM frequency coming from the attiny13a. I.e., how close would 200hz input match with the output frequency?
It’s my understanding that this driver doesn’t need fast pwm to avoid flickering issues so maybe RMM is right and we should choose a frequency that is better suited to the buck ic.
I'm awake!
A few things I'd personally do to check everything is functioning correctly hardware wise (to show that the problem may be firmware related):