Ricardo Seixas wrote:
>
> Hi PICers
>
>         Does anyone know a quick and dirty way (no Op Amp) to measure a low
> battery condition ?
>         Let's me explain:
>         I've built a portable camber meter using a 16F84 that's powered by
> a 9V battery and regulated down to 5V with a 7805, now I'm thinking to
> implement a simple low voltage indicator that drives a pin (High or Low)
> when battery reachs 5.5V.
>         This pin must be shared, since all pins are already used :(
>         It's no funny when you're in the middle of a camber adjustment and
> the battery dies ...
>         Any sugestions ?
>
> Thanks
>
> Ricardo Seixas
>

Two resistors as a voltage divider on an input. Choose the values so the
input will 'trip' from high to low when the battery goes low. It won't
be
very accurate, but it will be cheap & simple.

--
Friendly Regards

Tjaart van der Walt
mailto:tjaart@wasp.co.za
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