General Description

The ASM1834 supervisors simultaneously monitor both 3.3V and 5V power sources and generate reset signals when either supply is out of tolerance. When an out-of-tolerance condition is detected, the output-reset signal of the affected supply becomes active and resets the system microprocessor/microcontroller. On power-up and after the supply voltage returns to an in-tolerance condition, the reset signal remains active for approximately 350ms. This allows the power supply and system microprocessor to stabilize.

Key Features

• Monitors 5V and 3.3V supplies simultaneously

• 5V and 3.3V power-on reset

• 350ms reset time

• Debounced pushbutton reset input

• Push-pull CMOS output

• ASM1834, ASM1834D

• Eliminates external pull-up resistors

• Active LOW (ASM1834), HIGH (ASM1834D)

• Open Drain Output

• ASM1834A

• Active LOW

• Selectable 5V and 3.3V trip point tolerance

• Internal power drawn from highest input voltage, 5V or 3.3V

• Precision temperature-compensated voltage reference and comparator

• Low cost surface mount SO, compact MicroSO and DIP packages.

• Wide operating temperature, -40°C to +85°C

Applications

• Microprocessors

• PDAs, Hand-held PCs

• Embedded Controllers

• Telecommunication Systems

• Power Supplies

• Wireless / Cellular Systems

• Networking Hardware