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 digital systems connected by twisted pair lines, they have a differential input designed to reject large common mode signals 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 capacitor 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
± 10% supply voltage variations.
Features
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Operation from a single +5V logic supply
Input voltage range of ± 15V
Strobe low forces output to “1” state
High input resistance
Fanout of ten with TTL integrated circuits
Outputs can be wire OR’ed
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
© 1999 National Semiconductor Corporation
DS005797
www.national.com
DS7820A/DS8820A Dual Line Receiver
May 1999
