SN75ALS171, SN75ALS171A
TRIPLE DIFFERENTIAL BUS TRANSCEIVERS
SLLS056D – AUGUST 1987 – REVISED SEPTEMBER 1995
DW OR J PACKAGE
(TOP VIEW)
Three Bidirectional Transceivers
Driver Meets or Exceeds the Requirements
of ANSI EIA/TIA-422-B and RS-485 and ITU
Recommendation V.11
1R
1DE
1D
1B
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
1A
Two Skew Limits Available
RE
CDE
Designed to Operate Up to 20 Million Data
Transfers per Second (FAST-20 SCSI)
GND
GND
2R
V
CC
15 2B
High-Speed Advanced Low-Power Schottky
Circuitry
14
13
12
11
2DE
2D
2A
3B
3A
3D
Low Pulse Skew . . . 5 ns Max
3R
Designed for Multipoint Transmission on
Long Bus Lines in Noisy Environments
3DE
Features Independent Driver Enables and
Combined Receiver Enables
Wide Positive and Negative Input/Output
Bus Voltages Ranges
Driver Output Capacity . . . ±60 mA
Thermal Shutdown Protection
Driver Positive- and Negative-Current
Limiting
Receiver Input Impedances . . . 12 kΩ Min
Receiver Input Sensitivity . . . ±300 mV Max
Receiver Input Hysteresis . . . 60 mV Typ
Operates From a Single 5-V Supply
Glitch-Free Power-Up and Power-Down
Protection
description
The SN75ALS171 and the SN75ALS171A triple differential bus transceivers are monolithic integrated circuits
designed for bidirectional data communication on multipoint bus transmission lines. They are designed for
balanced transmission lines, and each driver meets ANSI Standards EIA/TIA-422-B and RS-485 and both the
drivers and receivers meet ITU Recommendation V.11. The SN75ALS171A is designed for FAST-20 SCSI and
can transmit or receive data pulses as short as 30 ns with a maximum skew of 5 ns.
The SN75ALS171 and the SN75ALS171A operate from a single 5-V power supply. The drivers and receivers
have individual active-high and active-low enables, respectively, which can be externally connected together
to function as a direction control. The driver differential output and the receiver differential input pairs are
connected internally to form differential input/output (I/O) bus ports that are designed to offer minimum loading
to the bus when the driver is disabled or V
common-mode voltage ranges making the device suitable for party-line applications.
is at 0 V. These ports feature wide positive and negative
CC
The SN75ALS171 and the SN75ALS171A 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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