DS34C87T CMOS Quad TRI-STATE
™
Differential Line Driver
May 1998
DS34C87T
CMOS Quad TRISTATE Differential Line Driver
General Description
The DS34C87T is a quad differential line driver designed for
digital data transmission over balanced lines. The
DS34C87T meets all the requirements of EIA standard
RS-422 while retaining the low power characteristics of
CMOS. This enables the construction of serial and terminal
interfaces while maintaining minimal power consumption.
The DS34C87T accepts TTL or CMOS input levels and
translates these to RS-422 output levels. This part uses spe-
cial output circuitry that enables the individual drivers to
power down without loading down the bus. This device has
separate enable circuitry for each pair of the four drivers.
The DS34C87T is pin compatible to the DS3487T.
All inputs are protected against damage due to electrostatic
discharge by diodes to V
CC
and ground.
Features
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TTL input compatible
Typical propagation delays: 6 ns
Typical output skew: 0.5 ns
Outputs won’t load line when V
CC
= 0V
Meets the requirements of EIA standard RS-422
Operation from single 5V supply
TRI-STATE outputs for connection to system buses
Low quiescent current
Available in surface mount
Connection and Logic Diagrams
Dual-In-Line Package
DS008576-2
Truth Table
Input
H
L
DS008576-1
Control
Input
H
H
L
Non-Inverting
Output
H
L
Z
Inverting
Output
L
H
Z
X
Top View
Order Number DS34C87TM or DS34C87TN
See NS Package Number M16A or N16E
L = Low logic state
H = High logic state
X = Irrelevant
Z = TRI-STATE (high performance)
TRI-STATE
®
is a registered trademark of National Semiconductor Corporation.
© 1998 National Semiconductor Corporation
DS008576
www.national.com