I'm looking around for the GPS chipset that uses the lowest
current. So far, if this survey is any guide,

http://yona_n.tripod.com/gps/gps-survey.html

the Philips ones appear to have the lowest consumption. If
anyone has an alternative I'd be glad to hear about it

But there's an added complication - the client wants the GPS
part to be asleep most of the time (to save batteries) and update
the GPS data to the PIC every 10 - 20 seconds. This seems to
be not possible, as the way I read it, if you power-down the GPS,
it takes at least 45 seconds after power-up for "time to first fix".
Is that correct, or is there a work-around ?

Meaning that in the client's application the GPS would have to
be on all the time. His original intention was for a unit to run for
15 - 20 days on 3 or 4 AA batteries (and it has other power-
hungry things to do as well, not just GPS) but it looks to me as
if you could quite easily stuff a set of batteries in half a day. He's
short of space too, otherwise I'd suggest a larger battery. Even
6 x AA is going to be pushing it

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