On Wed, 21 Jan 1998 07:35:12 -0500, you wrote:

>Here's a handful of  ideas:
>
>1. Check out Raychems polyswitches - although the SRP series is rated
>too low for you application, you may
>    be able to use the RUE series (assuming you can put this outside of
>the battery pack).
>
>2. Put a mosfet in series with the battery voltage, sense the battery
>voltage with a micro/low power voltage
>    comparator, and then turn the mosfet off when the voltage begins to
>collapse - or sense the current w/ a
>    low power shunt and do the same.  You would probably us a p-channel
>fet and pull the gate low during normal
>    operation, this way you won't need a charge pump to drive the
>n-channel above the battery voltage.
No need for P channel or charge pumps - remember that in a battery
pack you could switch the negative rail.

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