DS1239

DS1239 MicroManager Chip www.dalsemi.com 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 applications Accurate 10% power supply monitoring Optional 5% power supply monitoring designated DS1239-5 Provides orderly shutdown in nonvolatile microprocessor applications Supplies necessary control for low-power “stop mode” in battery operate hand-held applications Standard 16-pin DIP or space-saving 16-pin SOIC Optional industrial temperature range -40°C to +85°C PIN ASSIGNMENT VBAT VCCO VCC GND PF PF WC/SC PSI 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 PSO RST PBRST CEI VBAT VCCO CEO VCC GND ST PF NMI PF WC/SC IN PSI 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 PSO RST PBRST CEI CEO ST NMI IN DS1239 16-Pin DIP (300-mil) See Mech. Drawings Section DS1239 16-Pin SOIC (300-mil) See Mech. Drawings Section PIN 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 C...