SN75LBC179, SN65LBC179, SN65LBC179Q
LOW-POWER DIFFERENTIAL LINE DRIVER AND RECEIVER PAIRS
SLLS173C – JANUARY 1994 – REVISED JANUARY 2000
D OR P PACKAGE
(TOP VIEW)
Designed for High-Speed Multipoint Data
Transmission Over Long Cables
Operate With Pulse Widths as Low
as 30 ns
V
A
B
Z
Y
1
2
3
4
8
7
6
5
CC
R
Low Supply Current . . . 5 mA Max
D
Meets or Exceeds the Standard
Requirements of ANSI RS-485 and
ISO 8482:1987(E)
GND
Function Tables
Common-Mode Voltage Range of –7 V
to 12 V
DRIVER
INPUT
D
OUTPUTS
Positive- and Negative-Output Current
Limiting
Y
Z
H
L
H
L
L
H
Driver Thermal Shutdown Protection
Pin Compatible With the SN75179B
RECEIVER
DIFFERENTIAL INPUTS OUTPUT
description
A–B
≥ 0.2 V
R
H
?
L
H
The SN65LBC179, SN65LBC179Q,
and
V
ID
–0.2 V < V < 0.2 V
SN75LBC179differential driver and receiver pairs
are monolithic integrated circuits designed for
bidirectional data communication over long
cables that take on the characteristics of
transmission lines. They are balanced, or
differential, voltage mode devices that meet or
exceed the requirements of industry standards
ANSI RS-485 and ISO 8482:1987(E). Both
devices are designed using TI’s proprietary
LinBiCMOS with the low power consumption of
CMOS and the precision and robustness of
bipolar transistors in the same circuit.
ID
≤ – 0.2 V
V
ID
Open circuit
H = high level,
? = indeterminate
L = low level,
†
logic symbol
8
7
2
3
A
B
R
D
6
5
Z
Y
The SN65LBC179, SN65LBC179Q,
and
SN75LBC179 combine a differential line driver
and differential line receiver and operate from a
single 5-V supply. The driver differential outputs
and the receiver differential inputs are connected
to separate terminals for full-duplex operation and
are designed to present minimum loading to the
†
This symbol is in accordance with ANSI/IEEE Std 91-1984
and IEC Publication 617-12.
logic diagram (positive logic)
8
2
A
B
bus when powered off (V
= 0). These parts
CC
R
D
7
feature a wide common-mode voltage range
making them suitable for point-to-point or
multipoint data bus applications. The devices also
provide positive- and negative-current limiting
andthermalshutdownforprotectionfromlinefault
conditions. Thelinedrivershutsdownatajunction
temperature of approximately 172°C.
5
6
3
Y
Z
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
LinBiCMOS is a trademark of Texas Instruments Incorporated.
Copyright 2000, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
1
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