SN75ALS1177, SN75ALS1178
DUAL DIFFERENTIAL DRIVERS AND RECEIVERS
SLLS154B – MARCH 1993 – REVISED FEBRUARY 2001
SN75ALS1177 . . . N OR NS PACKAGE
(TOP VIEW)
Meet or Exceed Standards TIA/EIA-422-B
and TIA/EIA-485-A
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
2B
Driver Common-Mode Output Voltage
Range of –7 V to 12 V
GND
Thermal Shutdown Protection
SN75ALS1178 . . . N OR NS PACKAGE
(TOP VIEW)
Driver 3-State Outputs Active-High Enable
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
1DE
2R
Receiver High Input
Impedance . . . 12 kΩ Min
2DE
2Z
2A
Receiver 3-State Outputs Active-Low
Enable for SN75ALS1177 Only
2Y
2D
2B
GND
Operate From Single 5-V Supply
description
The SN75ALS1177 and SN75ALS1178 dual differential drivers and receivers are integrated circuits designed
for bidirectional data communication on multipoint bus transmission lines. They are designed for balanced
transmission lines and meet standards TIA/EIA-422-B and TIA/EIA-485-A.
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.
AVAILABLE OPTIONS
PACKAGED DEVICES
PLASTIC
DIP
PLASTIC
SMALL OUTLINE
(NS)
T
A
(N)
SN75ALS1177N
SN75ALS1178N
SN75ALS1177NSR
SN75ALS1178NSR
0°C to 70°C
The NS package is only available taped and reeled. Add the
suffix R to the device type (e.g., SN75ALS1177NSR).
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 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.
1
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