ON Semiconductor MC74AC157, MC74ACT157 Technical data
查询MC74AC157DR2供应商
MC74AC157, MC74ACT157
Quad 2−Input Multiplexer
The MC74AC157/74ACT157 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 MC74AC157/74ACT157 can also be used as a function
generator.
Features
• Outputs Source/Sink 24 mA
• ′ACT157 Has TTL Compatible Inputs
• Pb−Free Packages are Available*
16
http://onsemi.com
PDIP−16
N SUFFIX
CASE 648
1
V
CC
SI0aI
I
E
0cI1cZcI0dI1dZd
1516 14 13 12 11 10
21 34567
1aZaI0bI1bZb
9
8
GND
Figure 1. Pinout: 16−Lead Packages Conductors
(Top View)
TRUTH TABLE
Inputs Outputs
E S I
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 = Immaterial
I
0
1
Z
SOIC−16
16
1
16
1
16
1
D SUFFIX
CASE 751B
TSSOP−16
DT SUFFIX
CASE 948F
EIAJ−16
M SUFFIX
CASE 966
PIN NAMES
PIN
I0a−I
I1a−I
E
S
Za−Z
0d
1d
d
FUNCTION
Source 0 Data Inputs
Source 0 Data Inputs
Enable Input
Select Input
Outputs
DEVICE MARKING INFORMATION
See general marking information in the device marking
section on page 3 of this data sheet.
*For additional information on our Pb−Free strategy and soldering details, please
download the ON Semiconductor Soldering and Mounting Techniques
Reference Manual, SOLDERRM/D.
Semiconductor Components Industries, LLC, 2005
January, 2005 − Rev. 6
1 Publication Order Number:
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 6 of this data sheet.
MC74AC157/D
MC74AC157, MC74ACT157
EI0aI1aI0bI
S
Z
a
Figure 2. Logic Symbol
FUNCTIONAL DESCRIPTION
The MC74AC157/74ACT157 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
MC74AC157/74ACT157 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:
I
0a
I
1a
I
0b
I
1b
I
0c
I0cI1cI0dI
1b
Z
Z
b
c
Z
a
Zb = E•(I
Z
c
Zd = E•(I
Z
d
= E•(I
= E•(I
1d
•S+I0a•S)
1a
•S+I0b•S)
1b
•S+I0c•S)
1c
•S+I0d•S)
1d
A common use of the MC74AC157/74ACT157 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
MC74AC157/74ACT157 can generate any four of the
sixteen different functions of two variables with one
variable common. This is useful for implementing gating
functions.
I
1c
I
0d
I
1d
E S
Z
a
NOTE: This diagram is provided only for the understanding of logic
operations and should not be used to estimate propagation delays.
Z
b
Z
c
Figure 3. Logic Diagram
http://onsemi.com
2
Z
d
MC74AC157, MC74ACT157
r,f
AC Devices exce t Schmitt In uts
In ut Rise and Fall Time (Note 2)
MARKING DIAGRAMS
PDIP−16 SOIC−16 TSSOP−16 EIAJ−16
MC74AC157N
AWLYYWW
AC157
AWLYWW
AC
157
74AC157
ALYW
ALYW
MC74ACT157N
AWLYYWW
ACT157
AWLYWW
ACT
157
74ACT157
ALYW
ALYW
A = Assembly Location
WL, L = Wafer Lot
YY, Y = Year
WW, W = Work Week
MAXIMUM RATINGS
Symbol Parameter Value Unit
V
CC
V
IN
V
OUT
I
IN
I
OUT
I
CC
T
stg
Maximum ratings are those values beyond which device damage can occur. Maximum ratings applied to the device are individual stress limit
values (not normal operating conditions) and are not valid simultaneously . If these limits are exceeded, device functional operation is not implied,
damage may occur and reliability may be affected.
DC Supply Voltage (Referenced to GND) −0.5 to +7.0 V
DC Input Voltage (Referenced to GND) −0.5 to VCC +0.5 V
DC Output Voltage (Referenced to GND) −0.5 to VCC +0.5 V
DC Input Current, per Pin ±20 mA
DC Output Sink/Source Current, per Pin ±50 mA
DC VCC or GND Current per Output Pin ±50 mA
Storage Temperature −65 to +150 °C
RECOMMENDED OPERATING CONDITIONS
Symbol Parameter Min Typ Max Unit
V
CC
VIN, V
OUT
tr, t
f
tr, t
f
T
J
T
A
I
OH
I
OL
1. VIN from 30% to 70% VCC; see individual Data Sheets for devices that differ from the typical input rise and fall times.
2. V
from 0.8 V to 2.0 V; see individual Data Sheets for devices that differ from the typical input rise and fall times.
IN
pp
Supply Voltage
′ACT 4.5 5.0 5.5
DC Input Voltage, Output Voltage (Ref. to GND) 0 − V
CC
V
V
VCC @ 3.0 V − 150 −
′AC 2.0 5.0 6.0
Input Rise and Fall Time (Note 1)
′AC Devices except Schmitt Inputs
VCC @ 4.5 V − 40 − ns/V
VCC @ 5.5 V − 25 −
Input Rise and Fall Time (Note 2)
′ACT Devices except Schmitt Inputs
VCC @ 4.5 V − 10 −
VCC @ 5.5 V − 8.0 −
ns/V
Junction Temperature (PDIP) − − 140 °C
Operating Ambient Temperature Range −40 25 85 °C
Output Current − High − − −24 mA
Output Current − Low − − 24 mA
http://onsemi.com
3
Loading...