1 Features
• Meets or exceeds the requirements of
TIA/EIA-422-B, TIA/EIA-485-A, and ITU
Recommendation V.11
• Bus voltage range: –7V to 12V
• Positive- and negative-current limiting
• Driver output capability: 60mA Max
• Driver thermal-shutdown protection
• Receiver input impedance: 12kΩ Min
• Receiver input sensitivity: ±200mV
• Receiver input hysteresis: 50mV typical
• Operates from single 5V supply
• Low power requirements

2 Description
The SN75179B is a differential driver and
receiver pair designed for balanced transmission-line
applications and meets TIA/EIA-422-B, TIA/EIA-485-
A, and ITU Recommendation V.11. The device is
designed to improve the performance of full-duplex
data communications over long bus lines.
The SN75179B driver output provides limiting for both
positive and negative currents. The receiver features
high input impedance, input hysteresis for increased
noise immunity, and input sensitivity of ±200mV over
a common-mode input voltage range of –7V to 12V.
The driver provides thermal shutdown for protection
from line fault conditions. Thermal shutdown is
designed to occur at a junction temperature of
approximately 150°C. The SN75179B is designed to
drive current loads of up to 60mA maximum.
The SN75179B is characterized for operation from
0°C to 70°C.