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Notice: The information in this document is subject to change without notice

Low Power, 3.3V/3.0V µP Reset

ASM1817

rev 1.5

February 2005

Application Information

Operation - Power Monitor

The ASM1817 detects out-of-tolerance power supply

conditions. It resets a processor during power-up, power-

down and issues a reset to the system processor when the

monitored power supply voltage is below the reset threshold.

RESET signal is asserted. On power-up, RESET is kept

active (HIGH) for approximatley 150ms after the power

supply voltage has reached the selected tolerance. This

allows the power supply and microprocessor to stablize

before RESET is released.

Figure 1: Typical Application

Microprocessor

RESET

RESET

ASM1817

Figure 2: Timing Diagram: Power-Up

RESET

tF

RESET

Figure 3: Timing Diagram: Power-Down