The AME8500 family allows the user to customize the CPU reset function without any external components. The user has a large choice of reset voltage thresholds, reset time intervals, and output driver configurations, all of which are preset at the factory. Each wafer is trimmed to the customer's specifications. These circuits monitor the power supply voltage of P based systems. When the power supply voltage drops below the voltage threshold a reset is asserted immediately (within an interval TD1). The reset remains asserted after the supply voltage rises above the voltage threshold for a time interval, TD2 . The reset output may be either active high (RESET) or active low (RESETB). The reset output may be configured as either push/pull or open drain. The state of the reset output is guaranteed to be correct for supply voltages greater than 1V. The AME8501 includes all the above functionality plus an overtemperature shutdown function. When the ambient temperature exceeds 800C a reset is asserted and remains asserted until the temperature falls below 600C.