The ADM13307 is a triple voltage supervisor designed to monitor up to three voltage levels in DSP and microprocessorbased systems. There are five models available， all of which feature a combination of internally pretrimmed undervoltage threshold options for monitoring 1.8 V， 2.5 V， 3.3 V， and 5 V supplies. There are also two adjustable input options with undervoltage thresholds of either 0.6 V or 1.25 V. The ADM13307-18， ADM13307-25， and ADM13307-33 models have two internally fixed thresholds and one externally programmable threshold via a resistor string. The ADM13307-4 and ADM13307-5 offer one internally fixed threshold and two externally programmable thresholds. See the Ordering Guide for a list of all available options. During power-up， RESET is asserted when the supply voltage exceeds 1.1 V. The device then monitors the SENSEv input pins and holds the RESET output low as long as the SENSEv pins remain below the rising threshold voltage， VIT+. Once the supplies monitored at the SENSEv inputs rise above their associated thresholds， the reset signal remains low for the reset timeout period before deasserting. Subsequently， if a voltage monitored by the SENSEv pins falls below its associated falling input threshold voltage， VIT?， the RESET output asserts.