DESCRIPTION
The DS1239 MicroManager provides all the necessary functions for power supply control and monitoring, reset control, and memory backup in microprocessor-based systems. Using the DS1239, an AC power switch is no longer required for microprocessor-based systems. A keyboard control system for power supply start up and shutdown is provided through the use of the Power Supply Control Input and Output. In other respects, the DS1239 is functionally identical to a DS1236 in the NMOS mode. For a complete description of the other DS1239 features, refer to the DS1236 data sheet.

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