Last week, I've been searching for the problem in energy harvesting IC. The schematics and layout looked very simple, however, I managed to make mistake here =).
I suspected that issue is in component values, because I tried to use the closest nominal values I had at the moment (i.e. instead of 4.7uF - 10uF, instead of 330pF - 470pF, etc,).
But, after I resoldered the most critical components , the situation was the same: the circuit just didn't want to start!!! - Pointing with oscilloscope into different nodes of circuit didn't help to understand "WHY?!".
Then I googled pictures for the evaluation kits and devBoards with this LTC chip, to see - what's difference there (that's the bonus side of designing circuits that already exist! ) . And at some moment, I noticed there, that inductor is placed with the 1-st pad in opposite direction. Later, when I rotated it 180° on all my 3 boards, everything started working like a charm! - I'll fix this in documentation.
Here is the screenshot from oscilloscope, which made me happy :)
Yellow line is voltage on Vout node, red line - voltage on Vstore node - everything just like in datasheet! I used ordinary power supply as power input, where I set 100mV voltage and current limit around 10mA)
The conlcusions are:
1) The reason of mistake was: I didn't pay attention, that coil is asymmetric, and one side have just a few turns, but the other - hundreds!! So, If I want it to increase voltage, then I need place side with few turns to low-voltage source :)
2) It's much simpler to solder 0603 component on 0805 footprint, than vice versa. Therefore if space allows, and I have not only 0603 but also lots of 0805 in my stock, for first prototypes better to use 0805 footprints.