NCP1232

NCP1232 Microprocessor Monitor The NCP1232 is a fully-integrated processor supervisor. It provides three important functions to safeguard processor functionality: precision power on/off reset control, watchdog timer and external reset override. On power-up, the NCP1232 holds the processor in the reset state for a minimum of 250 msec after VCC is within tolerance to ensure a stable system start-up. Microprocessor functionality is monitored by the on- board watchdog circuit. The microprocessor must provide a periodic low-going signal on the ST input. Should the processor fail to supply this signal within the selected time-out period (150 msec, 600 msec or 1200 msec), an out- of- control processor is indicated and the NCP1232 issues a processor reset as a result. The outputs of the NCP1232 are immediately driven active when the PB input is brought low by an external push-button switch or other electronic signal. When connected to a push-button switch, the NCP1232 provides contact debounce. The NCP1232 is packaged in a space-saving 8-pin plastic SOIC package and requires no external components. Features Precision Voltage Monitor (Adjustable +4.5 V or +4.75 V) Reset Pulse Width (250 msec Min) No External Components Adjustable Watchdog Timer (150 msec, 600 msec or 1.2 sec) Debounced Manual Reset Input for External Override Applications Computers Controllers Intelligent Instruments Automotive Systems Critical mP Power Monitoring http://onsemi.com 8 1 SO-8 D S...