REV. B

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reliable. However, no responsibility is assumed by Analog Devices for its

use, nor for any infringements of patents or other rights of third parties

which may result from its use. No license is granted by implication or

otherwise under any patent or patent rights of Analog Devices.

a

ADM1232

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781/329-4700

World Wide Web Site: http://www.analog.com

Fax: 781/326-8703

© Analog Devices, Inc., 1997

Microprocessor

Supervisory Circuit

FUNCTIONAL BLOCK DIAGRAM

GND

PB RESET

TOLERANCE

TD

RESET

ADM1232

RESET

GENERATOR

RESET

DEBOUNCE

WATCHDOG

TIMEBASE

SELECT

WATCHDOG

TIMER

5%/10%

TOLERANCE

SELECT

VREF

FEATURES

Superior Upgrade for MAX1232 and Dallas DS1232

Low Power Consumption (500

A max)

Adjustable Precision Voltage Monitor with +4.5 V and

+4.75 V Options

Adjustable STROBE Monitor with 150 ms, 600 ms or

1.2 sec Options

No External Components

APPLICATIONS

Microprocessor Systems

Portable Equipment

Computers

Controllers

Intelligent Instruments

Automotive Systems

Protection Against Damage Caused by

P Failure

GENERAL DESCRIPTION

The ADM1232 is a superior, pin-compatible upgrade for the

MAX1232 and the DS1232LP and DS1232. The Analog

Devices ADM1232 is a microprocessor monitoring circuit that

can monitor:

1. Microprocessor Supply Voltage.

2. Whether a Microprocessor has locked-up.

3. An External Interrupt.

The ADM1232 is available in four different packages:

1. The ADM1232ARM in an 8-lead microSOIC (RM-8).

2. The ADM1232AN in an 8-lead PDIP (N-8).

3. The ADM1232ARW in a 16-lead wide SOIC (R-16).

4. The ADM1232ARN is an 8-lead narrow SOIC (R-8).

ADM1232

ADM1232

STROBE

TOLERANCE

RESET

GND

TD

ADM1232

RESET

MICROPROCESSOR

STROBE

TOLERANCE

I/O

+5V

RESET

10k

+5V

Figure 1. Typical Supply Monitoring Application