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UM803

3-Pin Microprocessor Reset Circuits

UM803 SOT323/SOT23-3

General Description

The UM803 is a microprocessor (μP) supervisory circuit used to monitor the power supplies in μP

and digital systems. It provides excellent circuit reliability and low cost by eliminating external

components and adjustments when used with +5V, +3.3V, +3.0V or +2.5V powered circuits.

the reset threshold. Reset thresholds suitable for operation with a variety of supply voltages are

available.

The UM803 has an open-drain output stage. The UM803’s open-drain RESET

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output requires a

RESET

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Low supply current makes the UM803 ideal for use in portable equipment. The UM803 is available

in a 3-pin SOT323 and SOT23 package.

Applications

Features



Computers



Controllers



Portable/Battery-Powered Equipments



Intelligent Instruments



Critical μP and μC Power Monitoring



Automotive



No External Components



Power Supply Transient Immunity





+5V Supplies



Fully Specified Over Temperature



2μA Supply Current



140ms Minimum Power-On Reset Pulse Width



Available in One Output Configuration:

Open-Drain Active-Low RESET

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Output



3-Pin SOT323 and SOT23 Packages



Wide Operation Temperature: -40°C to +85°C

Pin Configurations

Top View

GND

1

RESET 2

3 VCC

3

XXX

2

1

Marking Pin1

M: Month Code

UM803

SOT323/SOT23-3