SN54ALS645A Datasheet, PDF (1/9 Pages) Texas Instruments – OCTAL BUS TRANSCEIVERS WITH 3-STATE OUTPUTS

SN54ALS645A, SN54AS645, SN74ALS645A, SN74AS645
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SDAS278 – JANUARY 1995
• Bidirectional Bus Transceivers in
High-Density 20-Pin Packages
• True Logic
• 3-State Outputs
• Package Options Include Plastic
Small-Outline (DW) Packages, Ceramic
Chip Carriers (FK), and Standard Plastic (N)
and Ceramic (J) 300-mil DIPs
description
These octal bus transceivers are designed for
asynchronous two-way communication between
data buses. These devices transmit data from the
A bus to the B bus or from the B bus to the A bus,
depending on the level at the direction-control
(DIR) input. The output-enable (OE) input can be
used to disable the device so that the buses are
effectively isolated.
SN54ALS645A, SN54AS645 . . . J PACKAGE
SN74ALS645A, SN74AS645 . . . DW OR N PACKAGE
(TOP VIEW)
DIR ₁
A1 ₂
A2 3
A3 4
A4 5
A5 6
A6 7
A7 8
A8 9
GND 10
20 ^V_CC
19 ^OE
18 B1
17 B2
16 B3
15 B4
14 B5
13 B6
12 B7
11 B8
SN54ALS645A, SN54AS645 . . . FK PACKAGE
(TOP VIEW)
The -1 version of the SN74ALS645A is identical
to the standard version, except that the
recommended maximum I_OL is increased to
48 mA. There is no -1 version of the
SN54ALS645A.
The SN54ALS645A and SN54AS645 are
characterized for operation over the full military
temperature range of – 55°C to 125°C. The
SN74ALS645A and SN74AS645 are
characterized for operation from 0°C to 70°C.
3 2 1 20 19
A3 ₄
18 ^B1
A4 ₅
17 ^B2
A5 6
16 B3
A6 7
15 B4
A7 8
14 B5
9 10 11 12 13
FUNCTION TABLE
INPUTS
OE DIR
OPERATION
L
L
B data to A bus
L
H A data to B bus
H
X
Isolation
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.
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Copyright © 1995, Texas Instruments Incorporated
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