This board implements the schematic shown on page 1 of the LTC3105 datasheet: http://cds.linear.com/docs/en/datasheet/3105fb.pdf See attached schematic. The header pins are positioned so as to plug easily into a 2.54mm pitch breadboard. The photovoltaic cell and battery would be attached externally using the header pins.
The LTC3105 is a step-up voltage converter with a low start-up voltage of 250mv. It includes Maximum Power Point Control (MPPC), which Linear Technologies advertises as being useful in solar applications.
Note: From what I've read, MPPC is less capable than full-blown MPPT. I haven't yet tried it, so I can't really say how effective it is or isn't. Anyone who has had experience with it, please post a comment. Perhaps in conjunction with a micro-controller, it may be possible to approximate MPPT by leveraging the chip's MPPC.
The intended purpose of this project is to harvest enough solar energy from only weak, ambient indoor light to power a mote using just the solar cell scavenged from a cheap $1 garden light (see attached photos). That's inherently harder to do than if the solar cell were exposed to direct sunlight, and so it's likely that some kind of voltage booster will be needed to harvest the available energy. Also, although Linear Technologies schematic shows the use of a rechargeable Lithium Ion battery, if possible I'd prefer to charge a super cap of some kind and run the mote from that. Any suggestions along those lines are, of course, very welcome.
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