Revised February 2000
DM74ALS257 • DM74ALS258
3-STATE Quad 1-of-2-Line Data Selector/Multiplexer
General Description
Features
These data selectors/multiplexers contain inverters and
drivers to supply full on-chip data selection to the four 3STATE outputs that can interface directly with data lines of
bus-organized systems. A 4-bit word selected from one of
two sources is routed to the four outputs. The
DM74ALS257 presents true data whereas the
DM74ALS258 presents inverted data to minimize propagation delay time.
■ Switching specifications at 50 pF
This 3-STATE output feature means that n-bit (paralleled)
data selectors with up to 258 sources can be implemented
for data buses. It also permits the use of standard TTL registers for data retention throughout the system.
■ Switching specifications guaranteed over full temperature and VCC range
■ Advanced oxide-isolated, ion-implanted Schottky TTL
process
■ Functionally and pin for pin compatible with Schottky
and low power Schottky TTL counterpart
■ Improved AC performance over Schottky and low power
Schottky counterparts
■ 3-STATE buffer-type outputs drive bus lines directly
■ Expand any data input point
■ Multiplex dual data buses
■ General four functions of two variables (one variable is
common)
■ Source programmable counters
Ordering Code:
Order Number
Package Number
Package Description
DM74ALS257M
M16A
16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow
DM74ALS257SJ
M16D
16-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
DM74ALS257N
N16E
16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
DM74ALS258M
M16A
16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow
DM74ALS258N
N16E
16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.
Connection Diagram
Function Table
Inputs
Output
Output Y
Select
A
B
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
Control
DM74ALS257 DM74ALS258
H = HIGH Level
L = LOW Level
X = Don't Care
Z = High Impedance (OFF)
© 2000 Fairchild Semiconductor Corporation
DS006227
www.fairchildsemi.com
DM74ALS257 • DM74ALS258 3-STATE Quad 1-of-2-Line Data Selector/Multiplexer
April 1984
DM74ALS257 • DM74ALS258
Logic Diagrams
DM74ALS257
DM74ALS258
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2
Supply Voltage
7V
Input Voltage
7V
Voltage Applied to Disabled Output
5.5V
Note 1: The “Absolute Maximum Ratings” are those values beyond which
the safety of the device cannot be guaranteed. The device should not be
operated at these limits. The parametric values defined in the Electrical
Characteristics tables are not guaranteed at the absolute maximum ratings.
The “Recommended Operating Conditions” table will define the conditions
for actual device operation.
0°C to +70°C
Operating Free Air Temperature Range
−65°C to +150°C
Storage Temperature Range
Typical θJA
N Package
73.0°C/W
M Package
102.0°C/W
Recommended Operating Conditions
Symbol
Parameter
Min
Nom
Max
Units
4.5
5
5.5
V
LOW Level Input Voltage
0.8
V
VCC
Supply Voltage
VIH
HIGH Level Input Voltage
VIL
2
V
IOH
HIGH Level Output Current
−2.6
mA
IOL
LOW Level Output Current
24
mA
TA
Free Air Operating Temperature
70
°C
0
Electrical Characteristics
over recommended operating free air temperature range. All typical values are measured at VCC = 5V, TA = 25°C.
Symbol
Parameter
Conditions
VIK
Input Clamp Voltage
VCC = 4.5V, II = −18 mA
VOH
HIGH Level
VCC = 4.5V
VOL
Output Voltage
IOH = −0.4 mA
LOW Level
VCC = 4.5V
Input Current at Maximum
Typ
2.4
3.3
Units
V
V
VCC − 2
V
IOL = 12 mA
0.25
0.4
IOL = 24 mA
0.35
0.5
V
0.1
mA
VCC = 5.5V, VIH = 7V
Input Voltage
Max
−1.5
IOH = −2.6 mA
Output Voltage
II
Min
V
IIH
HIGH Level Input Current
VCC = 5.5V, VIH = 2.7V
20
µA
IIL
LOW Level Input Current
VCC = 5.5V, VIL = 0.4V
−0.1
mA
IO
Output Drive Current
VCC = 5.5V, VO = 2.25V
−112
mA
IOZH
OFF-State Output Current
VCC = 5.5V,
HIGH Level Voltage Applied
VO = 2.7V
20
µA
OFF-State Output Current,
VCC = 5.5V,
LOW Level Voltage Applied
VO = 0.4V
−20
µA
IOZL
ICCH
ICCL
ICCZ
Supply
DM74ALS257 VCC = 5.5V
Current
DM74ALS258 Outputs OPEN
Supply
DM74ALS257
Current
DM74ALS258
Supply
DM74ALS257
Current
DM74ALS258
−30
Outputs HIGH
Outputs LOW
Outputs Disabled
3
3
6
mA
2.5
4
mA
8
12
mA
7
11
mA
9
14
mA
8
13
mA
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DM74ALS257 • DM74ALS258
Absolute Maximum Ratings(Note 1)
DM74ALS257 • DM74ALS258
Switching Characteristics DM74ALS257
over recommended operating free air temperature range
Symbol
tPLH
tPHL
Parameter
Conditions
Propagation Delay Time
VCC = 4.5V to 5.5V
LOW-to-HIGH Level Output
CL = 50 pF
Propagation Delay Time
RL = 500Ω
HIGH-to-LOW Level Output
tPLH
Propagation Delay Time
LOW-to-HIGH Level Output
tPHL
Propagation Delay Time
HIGH-to-LOW Level Output
tZH
tZL
tHZ
tLZ
From
To
Min
Max
Units
Data
Any Y
2
10
ns
Data
Any Y
2
12
ns
Select
Any Y
4
18
ns
Select
Any Y
5
22
ns
Any Y
4
16
ns
Any Y
5
18
ns
Any Y
2
10
ns
Any Y
3
15
ns
From
To
Min
Max
Units
Data
Any Y
2
8
ns
Data
Any Y
2
7
ns
Select
Any Y
3
20
ns
Select
Any Y
5
25
ns
Any Y
5
18
ns
Any Y
5
18
ns
Any Y
2
10
ns
Any Y
3
18
ns
Output Enable Time
Output
to HIGH Level
Control
Output Enable Time
Output
to LOW Level
Control
Output Disable Time
Output
from HIGH Level
Control
Output Disable Time
Output
from LOW Level
Control
Switching Characteristics DM74ALS258
over recommended operating free air temperature range
Symbol
tPLH
tPHL
Parameter
Conditions
Propagation Delay Time
VCC = 4.5V to 5.5V
LOW-to-HIGH Level Output
CL = 50 pF
Propagation Delay Time
RL = 500Ω
HIGH-to-LOW Level Output
tPLH
Propagation Delay Time
LOW-to-HIGH Level Output
tPHL
Propagation Delay Time
HIGH-to-LOW Level Output
tZH
tZL
tHZ
tLZ
Output Enable Time
Output
to HIGH Level
Control
Output Enable Time
Output
to LOW Level
Control
Output Disable Time
Output
from HIGH Level
Control
Output Disable Time
Output
from LOW Level
Control
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4
DM74ALS257 • DM74ALS258
Physical Dimensions inches (millimeters) unless otherwise noted
16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow
Package Number M16A
5
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DM74ALS257 • DM74ALS258
Physical Dimensions inches (millimeters) unless otherwise noted (Continued)
16-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
Package Number M16D
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6
DM74ALS257 • DM74ALS258 3-STATE Quad 1-of-2-Line Data Selector/Multiplexer
Physical Dimensions inches (millimeters) unless otherwise noted (Continued)
16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Package Number N16E
Fairchild does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and
Fairchild reserves the right at any time without notice to change said circuitry and specifications.
LIFE SUPPORT POLICY
FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD
SEMICONDUCTOR CORPORATION. As used herein:
2. A critical component in any component of a life support
device or system whose failure to perform can be reasonably expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the
body, or (b) support or sustain life, and (c) whose failure
to perform when properly used in accordance with
instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the
user.
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7
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