Crystals

[BrianT]

I run a PIC16LF877A with a 3.6 volt lithium battery and a 4 MHz crystal. The crystal costs $0.50. It works just as well with or without the 10 pF crystal caps. Current draw in sleep is under 8 uA. The unit wakes frequently (via the SLEEP nn command) and runs for over a year on a Tadiran TL-5186 lithium button cell. A 16F877A runs close to the same current on 5 volts and also works down to about 3 volts.

HTH
Brian