SN75ALS1177, SN75ALS1178
DUAL DIFFERENTIAL DRIVERS AND RECEIVERS
SLLS154A – MARCH 1993 – REVISED MAY 1995
†
SN75ALS1177 . . . N OR NS PACKAGE
Meet or Exceed Standards EIA/TIA-422-B,
RS-485, CCITT Recommendation V.11
(TOP VIEW)
Designed for Multipoint Bus Transmission
on Long Bus Lines in Noisy Environments
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
1B
1A
V
CC
1D
1Y
1Z
DE
2Z
2Y
2D
Low Supply Current Requirement
50 mA Max
1R
RE
2R
Driver Positive- and Negative-Current
Limiting
2A
Driver Common-Mode Output Voltage
Range of –7 V to 12 V
2B
GND
Thermal Shutdown Protection
Driver 3-State Outputs Active-High Enable
†
SN75ALS1178 . . . N OR NS PACKAGE
(TOP VIEW)
Receiver Common-Mode Input Voltage
Range of –12 V to 12 V
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
V
CC
1B
1A
Receiver Input Sensitivity . . . ±200 mV
1D
1Y
1Z
Receiver Hysteresis . . . 50 mV Typ
1R
Receiver High Input Impedance
12 kΩ Min
1DE
2R
2DE
2Z
Receiver 3-State Outputs Active-Low
Enable for SN75ALS1177 Only
2A
2Y
2D
2B
Operate From Single 5-V Supply
GND
description
†
The NS package is only available in left-end taped and
reeled (SN75ALS1177NSLE and SN75ALS1178SNLE).
The SN75ALS1177 and SN75ALS1178 dual
differential drivers and receivers are monolithic
integrated circuits designed for bidirectional data
communication on multipoint bus transmission
lines. They are designed for balanced transmis-
sion lines and meet standards EIA/TIA-422-B,
RS-485, and CCITT Recommendation V.11.
The SN75ALS1177 combines dual 3-state differential line drivers and dual 3-state differential input line
receivers, both of which operate from a single 5-V power supply. The drivers and receivers have active-high
and active-low enables, respectively, which can be externally connected together to function as direction
control. The SN75ALS1178 drivers each have an individual active-high enable. Fail-safe design ensures that
when the receiver inputs are open, the receiver outputs are always high.
The SN75ALS1177 and SN75ALS1178 are characterized for operation from 0°C to 70°C.
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.
Copyright 1995, 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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