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
1
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
D
3-State Outputs Interface Directly With
System Bus
D
Provide Bus Interface From Multiple
Sources in High-Performance Systems
D
Package Options Include Plastic
Small-Outline (D) Packages, Ceramic Chip
Carriers (FK), and Standard Plastic (N) and
Ceramic (J) 300-mil DIPs
description
These data selectors/multiplexers are designed
to multiplex signals from 4-bit data sources to
4-output data lines in bus-organized systems. The
3-state outputs do not load the data lines when the
output-enable (OE) input is at a high logic level.
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.
FUNCTION TABLE
INPUTS
OUTPUT Y
OE
A /B
DATA
SN54ALS257A
SN74ALS257A
SN54ALS258A
SN74ALS258A
OE
A /B
A
B
SN74ALS257A
SN74AS257
SN74ALS258A
SN74AS258
H
X
X
X
Z
Z
L
L
L
X
L
H
L
L
H
X
H
L
L
H
X
L
L
H
L
H
X
H
H
L
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
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
A/B
1A
1B
1Y
2A
2B
2Y
GND
V
CC
OE
4A
4B
4Y
3A
3B
3Y
SN54ALS257A, SN54ALS258A . . . J PACKAGE
SN74ALS257A, SN74ALS258A, SN74AS257,
SN74AS258 . . . D OR N PACKAGE
(TOP VIEW)
SN54ALS257A, SN54ALS258A . . . FK PACKAGE
(TOP VIEW)
NC No internal connection
3
2 1 20 19
9 10 11 12 13
4
5
6
7
8
18
17
16
15
14
4A
4B
NC
4Y
3A
1B
1Y
NC
2A
2B
1A
A/B
NC
3Y
3B
OE
2Y
GND
NC
V
CC
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.
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
2
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
logic symbols
OE
MUX
2
1A
1
3
1B
EN
15
G1
1
1Y
4
5
2A
6
2B
2Y
7
11
3A
10
3B
3Y
9
14
4A
13
4B
4Y
12
A /B
1
OE
MUX
2
1A
1
3
1B
EN
15
G1
1
1Y
4
5
2A
6
2B
2Y
7
11
3A
10
3B
3Y
9
14
4A
13
4B
4Y
12
A /B
1
SN54ALS257A, SN74ALS257A,
SN74AS257
SN54ALS258A, SN74ALS258A,
SN74AS258
These symbols are in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.
Pin numbers shown are for the D, J, and N packages.
logic diagrams (positive logic)
4Y
3Y
2Y
1Y
A/B
OE
4B
4A
3B
3A
2B
2A
1B
1A
4
2
3
7
5
6
9
11
10
12
14
13
1
15
4Y
3Y
2Y
1Y
A /B
OE
4B
4A
3B
3A
2B
2A
1B
1A
4
2
3
7
5
6
9
11
10
12
14
13
1
15
SN54ALS257A, SN74ALS257A,
SN74AS257
SN54ALS258A, SN74ALS258A,
SN74AS258
Pin numbers shown are for the D, J, and N packages.
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
3
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage, V
CC
7 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input voltage, V
I
7 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Voltage applied to a disabled 3-state output
5.5 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maximum power dissipation at T
A
= 55
C (in still air) (see Note 1): D package
1.3 W
. . . . . . . . . . . . . . . . . . .
N package
1.1 W
. . . . . . . . . . . . . . . . . . .
Operating free-air temperature range, T
A
: SN54ALS257A, SN54ALS258A
55
C to 125
C
. . . . . . . . . . . . . .
SN74ALS257A, SN74ALS258A
0
C to 70
C
. . . . . . . . . . . . . . . . .
Storage temperature range, T
stg
65
C to 150
C
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTE 1: The maximum package power dissipation is calculated using a junction temperature of 150
C and a board trace length of 750 mils,
except for the N package, which has a trace length of zero.
recommended operating conditions
SN54ALS257A
SN54ALS258A
SN74ALS257A
SN74ALS258A
UNIT
MIN
NOM
MAX
MIN
NOM
MAX
VCC
Supply voltage
4.5
5
5.5
4.5
5
5.5
V
VIH
High-level input voltage
2
2
V
VIL
Low-level input voltage
0.7
0.8
V
IOH
High-level output current
1
2.6
mA
IOL
Low-level output current
12
24
mA
TA
Operating free-air temperature
55
125
0
70
C
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
4
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
TEST CONDITIONS
SN54ALS257A
SN54ALS258A
SN74ALS257A
SN74ALS258A
UNIT
MIN
TYP
MAX
MIN
TYP
MAX
VIK
VCC = 4.5 V,
II = 18 mA
1.5
1.5
V
VCC = 4.5 V to 5.5 V,
IOH = 0.4 mA
VCC2
VCC2
VOH
VCC = 4 5 V
IOH = 1 mA
2.4
3.3
V
VCC = 4.5 V
IOH = 2.6 mA
2.4
3.2
VOH
VCC = 4 5 V
IOL = 12 mA
0.25
0.4
0.25
0.4
V
VOH
VCC = 4.5 V
IOL = 24 mA
0.35
0.5
V
IOZH
VCC = 5.5 V,
VO = 2.7 V
20
20
A
IOZL
VCC = 5.5 V,
VO = 0.4 V
20
20
A
II
VCC = 5.5 V,
VI = 7 V
0.1
0.1
mA
IIH
VCC = 5.5 V,
VI = 2.7 V
20
20
A
IIL
VCC = 5.5 V,
VI = 0.4 V
0.1
0.1
mA
IO
VCC = 5.5 V,
VO = 2.25 V
20
112
30
112
mA
SN54ALS257A
Outputs high
3
8
3
6
SN54ALS257A,
SN74ALS257A
VCC = 5.5 V
Outputs low
8
12
8
12
ICC
SN74ALS257A
Outputs disabled
9
14
9
14
mA
ICC
SN54ALS258A
Outputs high
2.5
5
2.5
4
mA
SN54ALS258A,
SN74ALS258A
VCC = 5.5 V
Outputs low
7
11
7
11
SN74ALS258A
Outputs disabled
8
13
8
13
All typical values are at VCC = 5 V, TA = 25
C.
The output conditions have been chosen to produce a current that closely approximates one half of the true short-circuit output current, IOS.
switching characteristics (see Figure 1)
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
R1 = 500
,
R2 = 500
,
TA = MIN to MAX
UNIT
SN54ALS257A
SN74ALS257A
MIN
MAX
MIN
MAX
tPLH
A or B
Any Y
2
12
2
10
ns
tPHL
A or B
Any Y
2
14
2
12
ns
tPLH
A /B
Any Y
4
21
6
18
ns
tPHL
A /B
Any Y
6
25
6
22
ns
tPZH
OE
Any Y
3
20
4
16
ns
tPZL
OE
Any Y
4
22
5
18
ns
tPHZ
OE
Any Y
2
12
2
10
ns
tPLZ
OE
Any Y
2
35
4
15
ns
For conditions shown MIN or MAX, use the appropriate value specified under recommended operating conditions.
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
5
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
switching characteristics (see Figure 1)
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
R1 = 500
,
R2 = 500
,
TA = MIN to MAX
UNIT
SN54ALS258A
SN74ALS258A
MIN
MAX
MIN
MAX
tPLH
A or B
Any Y
1
12
2
8
ns
tPHL
A or B
Any Y
2
9
2
7
ns
tPLH
A /B
Any Y
4
28
5
25
ns
tPHL
A /B
Any Y
5
25
6
20
ns
tPZH
OE
Any Y
3
20
4
18
ns
tPZL
OE
Any Y
5
21
5
18
ns
tPHZ
OE
Any Y
2
12
2
10
ns
tPLZ
OE
Any Y
3
37
4
18
ns
For conditions shown MIN or MAX, use the appropriate value specified under recommended operating conditions.
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage, V
CC
7 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input voltage, V
I
7 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Voltage applied to a disabled 3-state output
5.5 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maximum power dissipation at T
A
= 55
C (in still air) (see Note 1): D package
1.3 W
. . . . . . . . . . . . . . . . . . .
N package
1.1 W
. . . . . . . . . . . . . . . . . . .
Operating free-air temperature range, T
A
: SN74AS257, SN74AS258
0
C to 70
C
. . . . . . . . . . . . . . . . . . . . . .
Storage temperature range, T
stg
65
C to 150
C
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTE 1: The maximum package power dissipation is calculated using a junction temperature of 150
C and a board trace length of 750 mils,
except for the N package, which has a trace length of zero.
recommended operating conditions
SN74AS257
SN74AS258
UNIT
MIN
NOM
MAX
VCC
Supply voltage
4.5
5
5.5
V
VIH
High-level input voltage
2
V
VIL
Low-level input voltage
0.8
V
IOH
High-level output current
15
mA
IOL
Low-level output current
48
mA
TA
Operating free-air temperature
0
70
C
PDF 
ZIP