DS7820A/DS8820A

Dual Line Receiver

General Description

The DS7820A and the DS8820A are improved performance

digital line receivers with two completely independent units

fabricated on a single silicon chip. Intended for use with digi-

tal systems connected by twisted pair lines, they have a dif-

ferential input designed to reject large common mode sig-

nals while responding to small differential signals. The output

is directly compatible with TTL or LS integrated circuits.

The response time can be controlled with an external capaci-

tor to reject input noise spikes. The output state is a logic “1”

for both inputs open. Termination resistors for the twisted

pair line are also included in the circuit. Both the DS7820A

and the DS8820A are specified, worst case, over their full

operating temperature range (−55˚C to +125˚C and 0˚C to

70˚C respectively), over the entire input voltage range, for

Features

n Operation from a single +5V logic supply

n Strobe low forces output to “1” state

n High input resistance

n Fanout of ten with TTL integrated circuits

n Outputs can be wire OR’ed

n Series 54/74 compatible

Connection Diagram

Dual-in-Line Package

DS005797-2

Note 1: Pin 7 connected to bottom of cavity package.

Top View

Order Number DS7820AJ or DS8820AN See NS Package Number J14A or N14A

For Complete Military 883 Specificatons, See RETS Data Sheet.

Order Number DS7820AJ/883

See NS Package Number J14A or W14B

May 1999

© 1999 National Semiconductor Corporation

DS005797

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