Semiconductor Components Industries, LLC, 2002
February, 2002 Rev. 8
1
Publication Order Number:
SN74LS157/D
SN74LS157
Quad 2-Input Multiplexer
The LSTTL/MSI SN74LS157 is a high speed Quad 2-Input
Multiplexer. Four bits of data from two sources can be selected using
the common Select and Enable inputs. The four buffered outputs
present the selected data in the true (non-inverted) form. The LS157
can also be used to generate any four of the 16 different functions of
two variables. The LS157 is fabricated with the Schottky barrier diode
process for high speed and is completely compatible with all
ON Semiconductor TTL families.
Schottky Process for High Speed
Multifunction Capability
Non-Inverting Outputs
Input Clamp Diodes Limit High Speed Termination Effects
Special Circuitry Ensures Glitch Free Multiplexing
ESD > 3500 Volts
GUARANTEED OPERATING RANGES
Symbol
Parameter
Min
Typ
Max
Unit
V
CC
Supply Voltage
4.75
5.0
5.25
V
T
A
Operating Ambient
Temperature Range
0
25
70
C
I
OH
Output Current High
0.4
mA
I
OL
Output Current Low
8.0
mA
LOW
POWER
SCHOTTKY
SOIC
D SUFFIX
CASE 751B
PLASTIC
N SUFFIX
CASE 648
16
1
16
1
SOEIAJ
M SUFFIX
CASE 966
16
1
Device
Package
Shipping
ORDERING INFORMATION
SN74LS157N
16 Pin DIP
2000 Units/Box
SN74LS157D
SOIC16
38 Units/Rail
SN74LS157DR2
SOIC16
2500/Tape & Reel
SN74LS157M
SOEIAJ16
See Note 1
SN74LS157MEL
SOEIAJ16
1. For ordering information on the EIAJ version of
the SOIC package, please contact your local
ON Semiconductor representative.
See Note 1
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SN74LS157
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2
Figure 1. Connection Diagram DIP (TOP VIEW)
Common Select Input
Enable (Active LOW) Input
Data Inputs from Source 0
Data Inputs from Source 1
Multiplexer Outputs
S
E
I
0a
I
0d
I
1a
I
1d
Z
a
Z
d
1.0 U.L.
1.0 U.L.
0.5 U.L.
0.5 U.L.
10 U.L.
0.5 U.L.
0.5 U.L.
0.25 U.L.
0.25 U.L.
5 U.L.
NOTES: a) 1 TTL Unit Load (U.L.) = 40
m
A HIGH/1.6 mA LOW.
HIGH
LOW
(Note a)
LOADING
PIN NAMES
V
CC
= PIN 16
GND = PIN 8
NOTE:
The Flatpak version has the same
pinouts (Connection Diagram) as
the Dual In-Line Package.
14
13
12
11
10
9
1
2
3
4
5
6
7
16
15
8
V
CC
S
E
I
0c
I
1c
Z
c
I
1d
I
0d
Zd
I
0a
I
1a
Z
a
I
0b
I
1b
Z
b
GND
Figure 2. Logic Symbol
15 2 3 5 6 14 13 11 10
1
4
7
12
9
E I
0a
I
1a
I
0b
I
1b
I
0c
I
1c
I
0d
I
1d
Z
a
Z
b
Z
c
Z
d
S
SN74LS157
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3
Figure 3. Logic Diagram
14
1
2
6
7
3
4
5
9
11
12
10
13
15
V
CC
= PIN 16
GND = PIN 8
= PIN NUMBERS
FUNCTIONAL DESCRIPTION
The LS157 is a Quad 2-Input Multiplexer fabricated with
the Schottky barrier diode process for high speed. It selects
four bits of data from two sources under the control of a
common Select Input (S). The Enable Input (E) is active
LOW. When E is HIGH, all of the outputs (Z) are forced
LOW regardless of all other inputs.
The LS157 is the logic implementation of a 4-pole,
2-position switch where the position of the switch is
determined by the logic levels supplied to the Select Input.
The logic equations for the outputs are:
Z
a
= E
(I
1a
S + I
0a
S) Z
b
= E
(I
1b
S + I
0b
S)
Z
c
= E
(I
1c
S + I
0c
S)
Z
d
= E
(I
1d
S + I
0d
S)
A common use of the LS157 is the moving of data from
two groups of registers to four common output busses. The
particular register from which the data comes is determined
by the state of the Select Input. A less obvious use is as a
function generator. The LS157 can generate any four of
the 16 different functions of two variables with one variable
common. This is useful for implementing highly irregular
logic.
TRUTH TABLE
ENABLE
SELECT
INPUT
INPUTS
OUTPUT
E
S
I
0
I
1
Z
H
X
X
X
L
L
H
X
L
L
L
H
X
H
H
L
L
L
X
L
L
L
H
X
H
H = HIGH Voltage Level
L = LOW Voltage Level
X = Don't Care
SN74LS157
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4
DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE
(unless otherwise specified)
Limits
Symbol
Parameter
Min
Typ
Max
Unit
Test Conditions
V
IH
Input HIGH Voltage
2.0
V
Guaranteed Input HIGH Voltage for
All Inputs
V
IL
Input LOW Voltage
0.8
V
Guaranteed Input LOW Voltage for
All Inputs
V
IK
Input Clamp Diode Voltage
0.65
1.5
V
V
CC
= MIN, I
IN
= 18 mA
V
OH
Output HIGH Voltage
2.7
3.5
V
V
CC
= MIN, I
OH
= MAX, V
IN
= V
IH
or V
IL
per Truth Table
V
Output LOW Voltage
0.25
0.4
V
I
OL
= 4.0 mA
V
CC
= V
CC
MIN,
V
V
or V
V
OL
Output LOW Voltage
0.35
0.5
V
I
OL
= 8.0 mA
V
IN
= V
IL
or V
IH
per Truth Table
I
IH
Input HIGH Current
I
0
, I
1
E, S
20
40
A
V
CC
= MAX, V
IN
= 2.7 V
I
IH
I
0
, I
1
E, S
0.1
0.2
mA
V
CC
= MAX, V
IN
= 7.0 V
I
IL
Input LOW Current
I
0
, I
1
E, S
0.4
0.8
mA
V
CC
= MAX, V
IN
= 0.4 V
I
OS
Short Circuit Current (Note 2)
20
100
mA
V
CC
= MAX
I
CC
Power Supply Current
16
mA
V
CC
= MAX
2. Not more than one output should be shorted at a time, nor for more than 1 second.
AC CHARACTERISTICS
(T
A
= 25
C)
Limits
Symbol
Parameter
Min
Typ
Max
Unit
Test Conditions
t
PLH
t
PHL
Propagation Delay
Data to Output
9.0
9.0
14
14
ns
Figure 2
t
PLH
t
PHL
Propagation Delay
Enable to Output
13
14
20
21
ns
Figure 1
V
CC
= 5.0 V
C
L
= 15 pF
t
PLH
t
PHL
Propagation Delay
Select to Output
15
18
23
27
ns
Figure 2
L
AC WAVEFORMS
Figure 1.
Figure 2.
V
IN
V
OUT
1.3 V
t
PHL
1.3 V
t
PLH
1.3 V
1.3 V
V
IN
V
OUT
1.3 V
t
PHL
1.3 V
t
PLH
1.3 V
1.3 V
SN74LS157
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5
PACKAGE DIMENSIONS
N SUFFIX
PLASTIC PACKAGE
CASE 64808
ISSUE R
NOTES:
1. DIMENSIONING AND TOLERANCING PER ANSI
Y14.5M, 1982.
2. CONTROLLING DIMENSION: INCH.
3. DIMENSION L TO CENTER OF LEADS WHEN
FORMED PARALLEL.
4. DIMENSION B DOES NOT INCLUDE MOLD FLASH.
5. ROUNDED CORNERS OPTIONAL.
A
B
F
C
S
H
G
D
J
L
M
16 PL
SEATING
1
8
9
16
K
PLANE
T
M
A
M
0.25 (0.010)
T
DIM
MIN
MAX
MIN
MAX
MILLIMETERS
INCHES
A
0.740
0.770
18.80
19.55
B
0.250
0.270
6.35
6.85
C
0.145
0.175
3.69
4.44
D
0.015
0.021
0.39
0.53
F
0.040
0.70
1.02
1.77
G
0.100 BSC
2.54 BSC
H
0.050 BSC
1.27 BSC
J
0.008
0.015
0.21
0.38
K
0.110
0.130
2.80
3.30
L
0.295
0.305
7.50
7.74
M
0
10
0
10
S
0.020
0.040
0.51
1.01
_
_
_
_
SN74LS157
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6
PACKAGE DIMENSIONS
D SUFFIX
PLASTIC SOIC PACKAGE
CASE 751B05
ISSUE J
NOTES:
1. DIMENSIONING AND TOLERANCING PER ANSI
Y14.5M, 1982.
2. CONTROLLING DIMENSION: MILLIMETER.
3. DIMENSIONS A AND B DO NOT INCLUDE
MOLD PROTRUSION.
4. MAXIMUM MOLD PROTRUSION 0.15 (0.006)
PER SIDE.
5. DIMENSION D DOES NOT INCLUDE DAMBAR
PROTRUSION. ALLOWABLE DAMBAR
PROTRUSION SHALL BE 0.127 (0.005) TOTAL
IN EXCESS OF THE D DIMENSION AT
MAXIMUM MATERIAL CONDITION.
1
8
16
9
SEATING
PLANE
F
J
M
R
X 45
_
G
8 PL
P
B
A
M
0.25 (0.010)
B
S
T
D
K
C
16 PL
S
B
M
0.25 (0.010)
A
S
T
DIM
MIN
MAX
MIN
MAX
INCHES
MILLIMETERS
A
9.80
10.00
0.386
0.393
B
3.80
4.00
0.150
0.157
C
1.35
1.75
0.054
0.068
D
0.35
0.49
0.014
0.019
F
0.40
1.25
0.016
0.049
G
1.27 BSC
0.050 BSC
J
0.19
0.25
0.008
0.009
K
0.10
0.25
0.004
0.009
M
0
7
0
7
P
5.80
6.20
0.229
0.244
R
0.25
0.50
0.010
0.019
_
_
_
_
SN74LS157
http://onsemi.com
7
PACKAGE DIMENSIONS
H
E
A
1
DIM
MIN
MAX
MIN
MAX
INCHES
---
2.05
---
0.081
MILLIMETERS
0.05
0.20
0.002
0.008
0.35
0.50
0.014
0.020
0.18
0.27
0.007
0.011
9.90
10.50
0.390
0.413
5.10
5.45
0.201
0.215
1.27 BSC
0.050 BSC
7.40
8.20
0.291
0.323
0.50
0.85
0.020
0.033
1.10
1.50
0.043
0.059
0
0.70
0.90
0.028
0.035
---
0.78
---
0.031
A
1
H
E
Q
1
L
E
_
10
_
0
_
10
_
L
E
Q
1
_
NOTES:
1. DIMENSIONING AND TOLERANCING PER ANSI
Y14.5M, 1982.
2. CONTROLLING DIMENSION: MILLIMETER.
3. DIMENSIONS D AND E DO NOT INCLUDE MOLD
FLASH OR PROTRUSIONS AND ARE MEASURED
AT THE PARTING LINE. MOLD FLASH OR
PROTRUSIONS SHALL NOT EXCEED 0.15 (0.006)
PER SIDE.
4. TERMINAL NUMBERS ARE SHOWN FOR
REFERENCE ONLY.
5. THE LEAD WIDTH DIMENSION (b) DOES NOT
INCLUDE DAMBAR PROTRUSION. ALLOWABLE
DAMBAR PROTRUSION SHALL BE 0.08 (0.003)
TOTAL IN EXCESS OF THE LEAD WIDTH
DIMENSION AT MAXIMUM MATERIAL CONDITION.
DAMBAR CANNOT BE LOCATED ON THE LOWER
RADIUS OR THE FOOT. MINIMUM SPACE
BETWEEN PROTRUSIONS AND ADJACENT LEAD
TO BE 0.46 ( 0.018).
M
L
DETAIL P
VIEW P
c
A
b
e
M
0.13 (0.005)
0.10 (0.004)
1
16
9
8
D
Z
E
A
b
c
D
E
e
L
M
Z
M SUFFIX
SOEIAJ PACKAGE
CASE 96601
ISSUE O
SN74LS157
http://onsemi.com
8
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without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular
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including without limitation special, consequential or incidental damages. "Typical" parameters which may be provided in SCILLC data sheets and/or
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PUBLICATION ORDERING INFORMATION
JAPAN: ON Semiconductor, Japan Customer Focus Center
4321 NishiGotanda, Shinagawaku, Tokyo, Japan 1410031
Phone: 81357402700
Email: r14525@onsemi.com
ON Semiconductor Website: http://onsemi.com
For additional information, please contact your local
Sales Representative.
SN74LS157/D
Literature Fulfillment:
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