© Semiconductor Components Industries, LLC, 2011

November, 2011 − Rev. 0

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Publication Order Number:

CAT871/D

CAT871, CAT872

Dual Input Reset Generator

Description

CAT871, CAT872 are dual input reset generators designed to restart

microprocessor and microcontroller based systems when the

watchdog timer or other resetting mechanisms have become disabled

or failed.

CAT871, CAT872 monitor two inputs and output an active low reset

pulse after both inputs have been active (logic low) for a factory preset

minimum time. The reset pulse width is 2.2 ms for CAT871 and 70 ms

for CAT872. Releasing either input from its active state before the

minimum timeout period resets the internal timer and both inputs must

return to being active before the timer will restart with a fresh count

down.

CAT871, CAT872’s open drain output is capable of sinking up to

3 mA of current and may be wire−OR’d with other open drain devices

to drive a common reset input.

Features

Compliant

Typical Applications

Figure 1. Application Schematic

http://onsemi.com

PIN CONNECTIONS

ULLGA−6

UL SUFFIX

CASE 613AF

MARKING DIAGRAM

(Top View)

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See detailed ordering and shipping information in the package

dimensions section on page 9 of this data sheet.

ORDERING INFORMATION

VDD

RESET

GND

MR1

MR2

NIC

1

X = Specific Device Code

M = Date Code

XM