SN65LBC179A, SN75LBC179A
LOW-POWER DIFFERENTIAL LINE DRIVER AND RECEIVER PAIRS
SLLS377C – MAY 2000 – REVISED JUNE 2001
1
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
D
High-Speed Low-Power LinBiCMOS
Circuitry Designed for Signaling Rates† of
up to 30 Mbps
D
Bus-Pin ESD Protection Exceeds 12 kV
HBM
D
Very Low Disabled Supply-Current
Requirements ...700 µA Max
D
Common-Mode Voltage Range of –7 V
to 12 V
D
Low Supply Current . . . 15 mA Max
D
Compatible With ANSI Standard
TIA/EAI-485-A and ISO8482: 1987(E)
D
Positive and Negative Output Current
Limiting
D
Driver Thermal Shutdown Protection
description
The SN65LBC179A and SN75LBC179A
differential 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 are compatible with ANSI standard
TIA/EIA-485-A and ISO 8482:1987(E). The A
version offers improved switching performance
over its predecessors without sacrificing
significantly more power.
The SN65LBC179A and SN75LBC179A combine
a differential line driver and differential input 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 bus
when powered off (VCC = 0). These parts feature a wide positive and negative 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 and thermal shutdown for protection from line fault conditions.
The SN65LBC179A is characterized over the industrial temperature range of –40°C to 85°C. The
SN75LBC179A is characterized for operation over the commercial temperature range of 0°C to 70°C.
†Signaling rate by TIA/EIA-485-A definition restrict transition times to 30% of the bit length, and much higher signaling rates may be achieved
without this requirement as displayed in the TYPICAL CHARACTERISTICS of this device.
Copyright 2001, 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.
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.
logic diagram (positive logic)
R
D
B
A
Z
Y
7
8
6
5
2
3
INPUT
DOUTPUTS
Y Z
DRIVER
DIFFERENTIAL INPUTS
A–B
VID ≥ 0.2 V
–0.2 V < VID < 0.2 V
VID ≤ – 0.2 V
Open circuit
OUTPUT
R
H
?
L
H
RECEIVER
H = high level, L = low level,
? = indeterminate
Function Tables
1
2
3
4
8
7
6
5
VCC
R
D
GND
A
B
Z
Y
SN65LBC179AD (Marked as BL179A)
SN65LBC179AP (Marked as 65LBC179A)
SN75LBC179AD (Marked as LB179A)
SN75LBC179AP (Marked as 75LBC179A)
(TOP VIEW)
H
L
Open
H
L
H
L
H
L