Description
VBAT VCCO VCC GND PF
PF
WC/ SC
PSI
IN
NMI ST
CEO CEI PBRST RST
PSO
- +3 Volt Battery Input - Switched SRAM Supply Output - +5 Volt Power Supply Input - Ground - Power Fail (Active High) - Power Fail (Active Low) - Wake-Up Control (Sleep) - Power Supply Control Input - Early Warning Input - Non-M
Features
- Provides necessary control for start up and shutdown of power supply from keyboard Holds microprocessor in check during power transients Halts and restarts an out-of-control microprocessor Monitors push button for external override Warns microprocessor of an impending power failure Converts CMOS SRAM into nonvolatile memory Unconditionally write-protects memory when power supply is out of tolerance Consumes less than 100 nA of battery current Controls external power switch for high current appli.
DS1239 Datasheet
