SN75ALS170, SN75ALS170A
TRIPLE DIFFERENTIAL BUS TRANSCEIVER
SLLS055D – AUGUST 1987 – REVISED SEPTEMBER 1995
DW PACKAGE
(TOP VIEW)
Three Bidirectional Transceivers
Driver Meets or Exceeds ANSI Standard
EIA/TIA-422-B and RS-485 and ITU
Recommendation V.11
1D
1DIR
NC
GND
NC
2D
2DIR
NC
1B
1A
NC
NC
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
Two Skew Limits Available
Designed to Operate Up to 20 Million Data
Transfers per Second (FAST-20 SCSI)
V
CC
High-Speed Advanced Low-Power Schottky
Circuitry
15 2B
14
13
12
11
2A
3B
3A
NC
Designed for Multipoint Transmission on
Long Bus Lines in Noisy Environments
3D
3DIR
Wide Positive and Negative Input/Output
Bus Voltage Ranges
NC – No internal connection
Driver Output Capacity . . . ±60 mA
J PACKAGE
(TOP VIEW)
Thermal Shutdown Protection
Driver Positive- and Negative-Current
Limiting
1D
1DIR
GND
2D
1B
1A
V
1
2
3
4
5
6
7
14
13
12
Receiver Input Impedances . . . 12 kΩ Min
Receiver Input Sensitivity . . . ±300 mV Max
Receiver Input Hysteresis . . . 60 mV Typ
Operate From a Single 5-V Supply
CC
11 2B
10 2A
2DIR
3D
9
8
3B
3A
Glitch-Free Power-Up and Power-Down
Protection
3DIR
Feature Independent Direction Controls for
Each Channel
description
The SN75ALS170 and SN75ALS170A triple differential bus transceivers are monolithic integrated circuits
designed for bidirectional data communication on multipoint bus transmission lines. It is designed for balanced
transmission lines and the driver meets ANSI Standards EIA/TIA-422-B and RS-485 and both the driver and
receiver meet ITU Recommendation V.11. The SN75ALS170A 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 SN75ALS170 and SN75ALS170A operate from a single 5-V power supply. The drivers and receivers have
active-high and active-low enables, respectively, which are internally connected together to function as a
direction control. The driver differential outputs and the receiver differential inputs 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
making the device suitable for party-line applications.
= 0. These ports feature wide positive and negative common-mode voltage ranges
CC
The SN75ALS170 and the SN75ALS170A are characterized for operation from 0°C to 70°C.
AVAILABLE OPTIONS
SKEW LIMIT
10 ns
PART NUMBER
SN75ALS170DW SN75ALS170J
SN75ALS170ADW
5 ns
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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