On Fri, 14 Nov 1997 12:22:32 -0600, you wrote:

>Thanks to everyone who responded to my inquire on PIC's lowest power
>scheme and the best timed method to wake PIC up from sleep mode. Advices
>were really exellent. I am going to try recalibrating of watchdog timer
>before powering PIC down. It will save some real estate (external timer
>or RTC) and hopefully some current. By the way, databook drawing for
>PIC16C63 shows that maximum current with WDT enabled is about 10uA (in
>0-70C and 5V). Is it really so? Is it applicable to other PICs (like
>16C556 I am going to use)?
>I have few other questions:
>1. What is the difference between PIC16Cxxx and PIC16LCxxx?
L versions are tested & guaranteed to run at low voltages 
>2. Pins configuration in power down mode.
Make sure there is no possibility of an input floating - this will
take lots of power. Set unconnected pins as outputs. Ensure inputs
have well defined levels at all times. In general, unless you can
arrange all inputs to be high, switch pullups off - any low input will
draw power through them. 

     ____                                                           ____
   _/ L_/  Mike Harrison / White Wing Logic / wwl@netcomuk.co.uk  _/ L_/
 _/ W_/  Hardware & Software design / PCB Design / Consultancy  _/ W_/
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