Maxim Integrated DS1236A-5

Description
The DS1236A MicroManager Chip is a device that provides power supply monitoring, reset control, and memory backup in microprocessor-based systems. It features an internal voltage reference and comparator circuit that monitors power supply status. When an out-of-tolerance condition occurs, the microprocessor reset and power-fail outputs are forced active, and static RAM control unconditionally write protects external memory. The DS1236A also provides early warning detection of a user-defined threshold by driving a non-maskable interrupt. External reset control is provided by a pushbutton reset input.

Features
Monitors pushbutton for external override
Warns microprocessor of an impending power failure
Holds microprocessor in check during power transients
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 at 25°C
Controls external power switch for high current applications
Accurate 10% power supply monitoring
Optional 5% power supply monitoring (designated DS1236A-5)
Provides orderly shutdown in nonvolatile microprocessor applications
Supplies necessary control for low-power "stop mode" in battery operated hand-held applications

Applications
Microprocessor-based systems
Power supply monitoring
Reset control
Memory backup
Nonvolatile memory
Early warning detection
External reset control