AUXILIARY INTEGRATED CIRCUIT FOR MICROPROCESSOR MANAGEMENT

摘要

A system which includes a microprocessor (or microcontroller) and an auxiliary chip which monitors the system power supply voltage and performs related functions for the microprocessor, and also provides a watchdog function. The auxiliary chip can be put to sleep by the microprocessor to minimize power consumption. The microprocessor can direct an interrupt to the auxiliary chip, which will cause the auxiliary chip to respond with a signal which indicates to the microprocessor whether power supply voltage is heading up or down. In one mode, the auxiliary chip sends an interrupt to the microprocessor when the power supply falls to a first level, and also resets the microprocessor when the supply voltage reaches a second preset level on the way up (i.e. while power is being restored). In a selectable second mode, the auxiliary chip resets the processor when the power supply is on the way down.