1

LTC699

s

s

1.5mA Maximum Supply Current

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SO-8 Packaging

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4.65V Precision Voltage Monitor

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Power OK/Reset Time Delay: 200ms

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Minimum External Component Count

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Performance Specified Over Temperature

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Superior Upgrade for MAX699

The LTC699 provides power supply monitoring for

microprocessor-based systems. The features include mi-

croprocessor reset and watchdog timing. Precise internal

voltage reference and comparator circuit monitor the

power supply line. When an out-of-tolerance condition

occurs, the RESET output is forced to active low. In

addition, the RESET output is guaranteed to remain logic

An internal watchdog timer is also available, which forces

the RESET output to active low when the watchdog input

is not toggled prior to the time-out period of 1.6 seconds.

The LTC699 is offered in DIP and surface mount packages.

DESCRIPTIO

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FEATURE

Microprocessor

Supervisory Circuit

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APPLICATI

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Critical

µP Power Monitoring

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Intelligent Instruments

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Computers and Controllers

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Automotive Systems

APPLICATI

TYPICAL

I

DAGRA

BLOCK

0.1µF

µP POWER

I/O LINE

µP RESET

µP

SYSTEM

0.1µF

500k

LTC699 TA1

GND

WDI

RESET

MICROPROCESSOR RESET AND WATCHDOG TIMING IN

A SINGLE CHIP FOR MICROPROCESSOR SYSTEMS.

+5V

LTC699

VCC

RESET PULSE

GENERATOR

WDI

1.3V

–

+

C1

OSC

RESET

LTC699 BD

GND

TRANSITION

DETECTOR

WATCHDOG

TIMER