HD74AC157
Quad 2-Input Multiplexer
REJ03D0252–0200Z
(Previous ADE-205-371 (Z))
Rev.2.00
Jul.16.2004
Description
The HD74AC157 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 outputs present the selected data in the true (noninverted) form. The
HD74AC157 can also be used as a function generator.
Features
•
Outputs Source/Sink 24 mA
•
Ordering Information
Part Name
Package Type
Package Code Package Abbreviation Taping Abbreviation (Quantity)
FP-16DAV
TTP-16DAV
FP
RP
T
EL (2,000 pcs/reel)
EL (2,500 pcs/reel)
ELL(2,000 pcs/reel)
HD74AC157AFPEL SOP-16 pin (JEITA)
HD74AC157TELL
TSSOP-16 pin
HD74AC157ARPEL SOP-16 pin (JEDEC) FP-16DNV
Notes: 1. Please consult the sales office for the above package availability.
2. The packages with lead-free pins are distinguished from the conventional products by adding V at the end of
the package code.
Pin Arrangement
S 1
I
0a
2
I
1a
3
Z
a
4
I
0b
5
I
1b
6
Z
b
7
GND 8
(Top view)
16 V
CC
15
E
14 I
0c
13 I
1c
12 Z
c
11 I
0d
10 I
1d
9 Z
d
Rev.2.00, Jul.16.2004, page 1 of 7
HD74AC157
Logic Symbol
E
S
I
0a
I
1a
I
0b
I
1b
I
0c
I
1c
I
od
I
1d
Z
a
Z
b
Z
c
Z
d
Pin Names
I
0a
to I
0d
I
1a
to I
1d
E
S
Z
a
to Z
d
Source 0 Data Inputs
Source 1 Data Inputs
Enable Input
Select Input
Outputs
Functional Description
The HD74AC157 is a quad 2-input multiplexer. 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 HD74AC157 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 shown below:
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 HD74AC157 is the moving of data from two groups of register 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 HD74AC157 can generate any four of the sixteen different functions of two variables with
one variable common. This is useful for implementing gating functions.
Truth Table
Inputs
E
H
L
L
L
L
H :
L :
X :
X
H
H
L
L
High Voltage Level
Low Voltage Level
Immaterial
S
X
X
X
L
H
I
0
X
L
H
X
X
I
1
L
L
H
L
H
Output
Z
Rev.2.00, Jul.16.2004, page 2 of 7
HD74AC157
Logic Diagram
I
0a
I
1a
I
0b
I
1b
I
0c
I
1c
I
0d
I
1d
E
S
Z
a
Z
b
Z
c
Z
d
Please note that this diagram is provided only for the understanding of logic operations and should not be
used to estimate propagation delays.
Absolute Maximum Ratings
Item
Supply voltage
DC input diode current
DC input voltage
DC output diode current
DC output voltage
DC output source or sink current
DC V
CC
or ground current per output pin
Storage temperature
Symbol
V
CC
I
IK
V
I
I
OK
V
O
I
O
I
CC
, I
GND
Tstg
Ratings
–0.5 to 7
–20
20
–0.5 to Vcc+0.5
–50
50
–0.5 to Vcc+0.5
±50
±50
–65 to +150
Unit
V
mA
mA
V
mA
mA
V
mA
mA
°C
V
I
= –0.5V
V
I
= Vcc+0.5V
V
O
= –0.5V
V
O
= Vcc+0.5V
Condition
Recommended Operating Conditions
Item
Supply voltage
Input and output voltage
Operating temperature
Input rise and fall time
(except Schmitt inputs)
V
IN
30% to 70% V
CC
Symbol
V
CC
V
I
, V
O
Ta
tr, tf
2 to 6
0 to V
CC
–40 to +85
8
Ratings
V
V
°C
ns/V
V
CC
= 3.0V
V
CC
= 4.5 V
V
CC
= 5.5 V
Unit
Condition
Rev.2.00, Jul.16.2004, page 3 of 7
HD74AC157
DC Characteristics
Item
Sym-
bol
V
IH
Vcc
(V)
3.0
4.5
5.5
V
IL
3.0
4.5
5.5
3.0
4.5
5.5
3.0
4.5
V
OL
5.5
3.0
4.5
5.5
3.0
4.5
Input leakage
current
Dynamic output
current*
Quiescent supply
current
I
IN
I
OLD
I
OHD
I
CC
5.5
5.5
5.5
5.5
5.5
min.
2.1
3.15
3.85
—
—
—
2.9
4.4
5.4
2.58
3.94
4.94
—
—
—
—
—
—
—
—
—
—
Ta = 25°C
°
typ.
1.5
2.25
2.75
1.50
2.25
2.75
2.99
4.49
5.49
—
—
—
0.002
0.001
0.001
—
—
—
—
—
—
—
max.
—
—
—
0.9
1.35
1.65
—
—
—
—
—
—
0.1
0.1
0.1
0.32
0.32
0.32
±0.1
—
—
8.0
Ta = –40 to
+85°C
°
min.
2.1
3.15
3.85
—
—
—
2.9
4.4
5.4
2.48
3.80
4.80
—
—
—
—
—
—
—
86
–75
—
max.
—
—
—
0.9
1.35
1.65
—
—
—
—
—
—
0.1
0.1
0.1
0.37
0.37
0.37
±1.0
—
—
80
µA
mA
mA
µA
V
V
OUT
= 0.1 V or V
CC
–0.1 V
Unit
Condition
Input Voltage
V
V
OUT
= 0.1 V or V
CC
–0.1 V
Output voltage
V
OH
V
IN
= V
IL
or V
IH
I
OUT
= –50
µA
V
IN
= V
IL
or V
IH
I
OH
= –12 mA
I
OH
= –24 mA
I
OH
= –24 mA
V
IN
= V
IL
or V
IH
I
OUT
= 50
µA
V
IN
= V
IL
or V
IH
I
OL
= 12 mA
I
OL
= 24 mA
I
OL
= 24 mA
V
IN
= V
CC
or GND
V
OLD
= 1.1 V
V
OHD
= 3.85 V
V
IN
= V
CC
or ground
*Maximum
test duration 2.0 ms, one output loaded at a time.
AC Characteristics: HD74AC157
Ta = +25°C
C
L
= 50 pF
Min
Typ
Max
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
7.0
5.5
6.5
5.0
7.0
5.5
6.5
5.5
5.0
4.0
5.0
4.0
11.5
9.0
11.0
8.5
11.5
9.0
11.0
9.0
8.5
6.5
8.0
6.5
Ta = –40°C to +85°C
C
L
= 50 pF
Min
Max
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
13.0
10.0
12.0
9.5
13.0
10.0
12.0
9.5
9.0
7.0
9.0
7.0
ns
ns
ns
ns
ns
ns
Item
Propagation delay
S to Z
n
Propagation delay
S to Z
n
Propagation delay
E
to Z
n
Propagation delay
E
to Z
n
Propagation delay
I
n
to Z
n
Propagation delay
I
n
to Z
n
Note:
Symbol
t
PLH
t
PHL
t
PLH
t
PHL
t
PLH
t
PHL
V
CC
(V)*
1
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
Unit
1. Voltage Range 3.3 is 3.3 V ± 0.3 V
Voltage Range 5.0 is 5.0 V ± 0.5 V
Rev.2.00, Jul.16.2004, page 4 of 7
HD74AC157
Capacitance
Item
Input capacitance
Power dissipation capacitance
Symbol
C
IN
C
PD
4.5
50.0
Typ
pF
pF
Unit
V
CC
= 5.5 V
V
CC
= 5.0 V
Condition
Rev.2.00, Jul.16.2004, page 5 of 7
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