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TELCOM SEMICONDUCTOR, INC.

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ECONOMONITOR™ – 3-PIN SYSTEM SUPERVISOR WITH POWER

SUPPLY MONITOR AND WATCHDOG

TC32M

WATCHDOG

TIMER

RS

GND

∆V

DETECTOR

DELAY

TIMER

TC32M

FEATURES

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Incorporates the Functionality of the Industry

Standard TC1232 (Processor Monitor, Watchdog

and Manual Override RESET Controller) into a

Small, Lower Cost Package

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Guards Against Unstable Processor Operation

Resulting from Power "Brown-Out"

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Automatically Halts and Restarts an Out-of-

Control Microprocessor

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Output can be Wire-ORed, or Hooked to Manual

RESET Push-button Switch

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Space-Saving 3-Pin TO-92 or SOT-223 Package

APPLICATIONS

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All Microprocessor-Based Systems

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Battery Powered Computers and Controllers

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Automotive Systems

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Intelligent Instruments

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Critical Processor Monitoring

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Embedded Controllers

ORDERING INFORMATION

Temperature

Part No.

Package

Range

TC32MCDB

SOT-223

0

°C to +70°C

TC32MCZB

TO-92

0

°C to +70°C

TC32MEDB

SOT-223

– 40

°C to +85°C

TC32MEZB

TO-92

– 40

°C to +85°C

PIN CONFIGURATIONS

1

1

2

4

3

23

GND

TC32MCDB

TC32MEDB

TC32MCZB

TC32MEZB

VDD

VDD

RS

FUNCTIONAL BLOCK DIAGRAM

TO-92

SOT-223

TYPICAL OPERATING CIRCUIT

TC32M-2 9/26/96

5V

RESET

PO.1

RESET

MICRO-

CONTROLLER

R2,10k

MICROCONTROLLER EXAMPLE

RS

TC32M

R1, 10k

GENERAL DESCRIPTION

The TC32M is a fully-integrated processor supervisor in

a 3-pin package. It provides three important functions to

safeguard processor sanity: precision power on/off RESET

control, watchdog timer and external RESET override.

On power-up, the TC32M holds the processor in the

tolerance to ensure a stable system start-up. Microproces-

sor sanity is monitored by the on-board watchdog circuit.

The microprocessor must provide a high-to-low level shift

(through an external resistor divider) on the RS pin of the

TC32M. Should the processor fail to supply this signal within

the specified timeout period (typically 700msec), an out-of-

control processor is indicated and the TC32M issues a

processor reset as a result.

The output of the TC32M can be wire-ORed with a push-

button switch (or electronic signal) to override the TC32M

and unconditionally reset the processor. When connected to

a push-button switch, the TC32M provides contact debounce.

The TC32M is packaged in a space-saving TO-92

or SOT-223 package. It provides all of the functionality of the

industry standard TC1232 in a smaller, lower cost configu-

ration.