>>
The circuit is a bait dispenser and will live in the bush, so solar is not
an option. <<

Sounds like a great application for solar.  You don't need full sunlight to
get *some* power out of solar cells.  Since your circuit only draws 290uA
average, just a little assist will go a long way to save battery life.

By the way, 290uA for 5 years comes out to 12.7 Amp-hours, and doesn't take
into account battery self discharge or shelf life.  That's a pretty beafy
battery, although I'm not that familiar with what's available in lithium
cells.

Also, how often does the bait reservoir need to be refilled?  It's hard to
imagine (but possible, I suppose) that this bait dispenser can be filled
with a 5 year supply of food that won't perish while sitting in a bush
somewhere.  If someone has to go refill the container, they could just as
well replace batteries while they're at it.  Either you haven't thought this
thru or there is a lot your not telling us.


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, olin@embedinc.com, http://www.embedinc.com

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