I have a design with some problems using LTC3130 -
https://www.analog.com/media/en/technical-documentation/data-sheets/3130f.pdfI laid out a straightforward circuit that I think follows the datasheet. On page 30 there's an example circuit that's basically the same as mine, but 5 supercaps and wider range PV input. The IC has features for MPPT and the input and output voltage ranges are wide. So I expect it's simple (haha, I'm awful). These parts are getting more sophisticated and I feel the design is more hands-off than before.
The plan is to connect a small solar battery, like a square foot size, and use <1A to charge up some supercapacitors. It's enough to keep a small load running overnight. Even on a cloudy/rainy day it charges at a trickle with the RUN/MPPT doing something useful even down to 4V. On a sunny day it gives something like 12V and everything is peachy. I've noticed before that SCs in parallel don't store power quite as satisfyingly as series, so I set it to output 15V and buck that later.
When I build a bunch of these pcbs, I get a couple that work as expected, but 5 or so of them output really low voltage, never really charging the supercapacitors. A couple others have been destructively failed with magic smoke and all. It's frustrating. Am I designing this thing poorly, against the spec? Maybe I should somehow limit the output current going into the supercapacitors. I also feel wary about a wide range at both input and output. Breaking the parts in assembly? My soldering skills are pretty average I feel, I usually do better than 50% yield though.
I don't really know how to troubleshoot this.