At 05:20 PM 10/12/99 EDT, you wrote: >Hello all! > >I need to run a PIC12C508-9 from a small 9 volt (pp3) battery. ( It will >spend most of its life in sleep mode with pull ups disabled for minimum >current consumption) Standard 78l05 regs would kill the battery in no time, >whilst the low current regulators are cost prohibitive in this application. >Zeners require too buch bias current? >Would a resistor in series be ok? If so what should I limit the current to >the PIC to? >(2 gpios have a 47k in series to the outside world! and are at "0" in sleep) TELCOM TC55 series--draw about 3 uA through the ground pin when the pic is in sleep or just idling. Get 'em from Digikey in 3.3 and 5 volt series. Run at 3.3 volts if you can--cuts power draw by the PIC's a LOT! We have been using the TC-55's almost exclusively, with NO complaints so far. GOOD and CHEAP. And they can output a hundred or so mA if you push them. kelly William K. Borsum, P.E. -- OEM Dataloggers and Instrumentation Systems & San Diego, California, USA