SN54ALS257A, SN54ALS258A, SN74ALS257A, SN74ALS258A, SN74AS257, SN74AS258
QUADRUPLE 2-LINE TO 1-LINE DATA SELECTORS/MULTIPLEXERS
WITH 3-STATE OUTPUTS
SDAS124C – APRIL 1982 – REVISED AUGUST 1996
SN54ALS257A, SN54ALS258A . . . J PACKAGE
SN74ALS257A, SN74ALS258A, SN74AS257,
3-State Outputs Interface Directly With
System Bus
SN74AS258 . . . D OR N PACKAGE
Provide Bus Interface From Multiple
Sources in High-Performance Systems
(TOP VIEW)
A/B
1A
1B
1Y
2A
2B
2Y
GND
V
CC
15 OE
1
2
3
4
5
6
7
8
16
Package Options Include Plastic
Small-Outline (D) Packages, Ceramic Chip
Carriers (FK), and Standard Plastic (N) and
Ceramic (J) 300-mil DIPs
4A
4B
14
13
12 4Y
3A
10 3B
3Y
description
11
These data selectors/multiplexers are designed
to multiplex signals from 4-bit data sources to
4-outputdatalinesinbus-organizedsystems. The
3-state outputs do not load the data lines when the
output-enable (OE) input is at a high logic level.
9
SN54ALS257A, SN54ALS258A . . . FK PACKAGE
(TOP VIEW)
The SN54ALS257A and SN54ALS258A are
characterized for operation over the full military
temperature range of –55°C to 125°C. The
SN74ALS257A, SN74ALS258A, SN74AS257,
and SN74AS258 are characterized for operation
from 0°C to 70°C.
3
2
1 20 19
18
4A
4B
NC
4Y
3A
1B
1Y
NC
2A
2B
4
5
6
7
8
17
16
15
14
9 10 11 12 13
NC – No internal connection
FUNCTION TABLE
OUTPUT Y
SN54ALS257A SN54ALS258A
INPUTS
DATA
SN74ALS257A
SN74AS257
SN74ALS258A
SN74AS258
OE A/B
A
B
H
L
L
L
L
X
L
X
L
X
X
X
L
Z
L
Z
H
L
L
H
X
X
H
L
H
H
H
L
H
H
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 1996, 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
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265