SN75ALS1177, SN75ALS1178
DUAL DIFFERENTIAL DRIVERS AND RECEIVERS
SLLS154B – MARCH 1993 – REVISED FEBRUARY 2001
D
D
D
D
D
D
D
D
D
D
D
D
D
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
Low Supply-Current Requirement
50 mA Max
Driver Positive- and Negative-Current
Limiting
Driver Common-Mode Output Voltage
Range of –7 V to 12 V
Thermal Shutdown Protection
Driver 3-State Outputs Active-High Enable
Receiver Common-Mode Input Voltage
Range of –12 V to 12 V
Receiver Input Sensitivity . . . ±200 mV
Receiver Hysteresis . . . 50 mV Typ
Receiver High Input
Impedance . . . 12 kΩ Min
Receiver 3-State Outputs Active-Low
Enable for SN75ALS1177 Only
Operate From Single 5-V Supply
1B
1A
1R
RE
2R
2A
2B
GND
1
16
2
15
3
14
4
13
5
12
6
11
7
10
8
9
VCC
1D
1Y
1Z
DE
2Z
2Y
2D
SN75ALS1178 . . . N OR NS PACKAGE
(TOP VIEW)
1B
1A
1R
1DE
2R
2A
2B
GND
1
16
2
15
3
14
4
13
5
12
6
11
7
10
8
9
VCC
1D
1Y
1Z
2DE
2Z
2Y
2D
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
TA
0°C to 70°C
PLASTIC
DIP
(N)
PLASTIC
SMALL OUTLINE
(NS)
SN75ALS1177N
SN75ALS1177NSR
SN75ALS1178N
SN75ALS1178NSR
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.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
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