On Fri, 19 Dec 1997 11:43:45 -0200, you wrote:

>I'm developing a battery operated device with 16C71 and I need the 16C71
>to turn the power off. I thought in a transistor controlled by RA4.
>Please take a look in the attached file (just 2K) and say if it's safe.
>Or, does anyone have a better idea?
>
>Regards,
>
>Octavio
>======================================================
>Octavio Nogueira  - e-mail:   nogueira@mandic.com.br
>http://www.geocities.com/~oct_nogueira
>"ProPic" Production PIC Programmer Windows under US$20
>======================================================
Why turn it off at all.. ? 
Put the CPU in sleep mode, woken by the watchdog or INT interrupt etc.
If you use a micropower 5v reg (e.g. Holtek HT1050 or similar chips
>from Ricoh, Telcom etc.), power when off will be about 5uA (WDT off),
15-20uA (WDT on)., which gives > 20Khours from a PP3/MN1604 battery
(500mAH). 

I  saw a neat trick at a seminar recently, using the RC osc, use
OSCOUT to drive a simple charge pump to hold the gate of a supply
switching fet on - doing a sleep instruction turns the supply off.
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