On Fri, Jun 3, 2011 at 5:04 PM, V G wrote: > On Fri, Jun 3, 2011 at 4:31 PM, Oli Glaser wrote= : > >> >> I think with the average use of the tuner and put to sleep in between, >> almost anything will do. >> I would do a rough calculation on average current consumption - you may >> find it's not much more than battery self discharge, and the amount to >> keep it "topped up" will be very small. > > > Thanks for putting it into perspective. I'll probably just go with a 100 > mAh Li polymer cell and a small solar panel and hook it up to a buck/boos= t > converter to charge/use the battery. > Specifically, I'm looking at something very simple like this: http://www.linear.com/product/LTC3531 I'll have a physical switch with two modes: (off or charge mode) solar pane= l -> battery OR (on mode) battery -> circuit. When "off", the battery would charge from the solar panel. I just fix the LTC3531 at 3.9V and it will charge the cell to that voltage in charge mode, or supply a steady 3.9V whe= n the switch is set to "on" mode. Need to simulate this chip in LTSpice. But I really like the simplicity of this chip. Don't like the DFN package though. Can anyone recommend another similar chi= p (single inductor, low external part count) chip with approx same specs, and leaded package so I can actually solder it? --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .