Datasheet
SGLS211A − OCTOBER 2003 − REVISED MAY 2008
2
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
description (continued)
The SN65LBC176 combines a 3-state, differential line driver and a differential input line receiver, both of which
operate from a single 5-V power supply. The driver and receiver have active-high and active-low enables,
respectively, which can externally connect together to function as a direction control. The driver differential
outputs and the receiver differential inputs connect internally to form a differential input/output (I/O) bus port that
is designed to offer minimum loading to the bus whenever the driver is disabled or V
CC
= 0. This port features
wide positive and negative common-mode voltage ranges, making the device suitable for party-line
applications. Very low device supply current can be achieved by disabling the driver and the receiver. Both the
driver and receiver are available as cells in the Texas Instruments LinASIC Library.
This transceiver is suitable for ANSI Standard RS-485 and ISO 8482:1987 (E) applications to the extent that
they are specified in the operating conditions and characteristics section of this data sheet. Certain limits
contained in the ANSI Standard RS-485 and ISO 8482:1987 (E) are not met or cannot be tested over the entire
extended temperature range.
logic diagram (positive logic)
D
RE
R
7
6
4
1
2
B
A
Bus
3
DE
schematics of inputs and outputs
Input
V
CC
EQUIVALENT OF EACH INPUT TYPICAL OF RECEIVER OUTPUT
Output
V
CC
V
CC
100 kΩ NOM
A Port Only
18 kΩ
NOM
3 kΩ
NOM
A
or
B
100 kΩ NOM
B Port Only
1.1 kΩ
NOM
TYPICAL OF A AND B I/O PORTS