Yes, I think we understand that, but yor specs leave something to be desired.Thanks for your input, but I am not interested in just getting charging to work, I want to understand why what works works best from engineering analysis.
I'm going to assume when you say pedal quite hard you mean 10mph and that the magnets are about 20 inches around the rim.
So I make the output 4.2 volts peak at 12 HZ. and around 30ma. peak.
Please correct me if I am wrong.
You should go back and re-read the data sheet. While it has several features not all of them need to be used, so the components are the same.This chip is more complicated, more difficult to work with 10 pins v. 6, extra components are required to fit into the tiny available space and because it is from Linear, it is perhaps too expensive, costing > 12x as much and re-layout of my PCB.
I'm sorry you already laid out your PCB.
Probably the most important is the start/stop voltage, because below this you get nothing.Even if this is the best chip for the job, I am looking to understand from engineering analysis why a cheaper, simpler solution like the LM27313 can be made to work as well and why the MCP1624 can cannot.
Start -- 27313 - 2.7v 1624 -.8v LT .4v
Stop -- 1.5v .35v .225v
Then maybe worry about how much power the chip uses:
27313 -2ma 1624 - 220 ua LT 200ua.
So you can google around and probably find lots of better ones by reading the data sheets. Try energy harvesting boost converter.