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DM74S157N

Part # DM74S157N
Description Encoders, Decoders, Multiplexers & Demultiplexers Qd 2to1
Category IC
Availability In Stock
Qty 40
Qty Price
1 + $0.25263
Manufacturer Available Qty
National Semiconductor Corp
Date Code: 8632
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National Semiconductor Corp
  • Shipping Freelance Stock: 10
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Technical Document


DISCLAIMER: The information provided herein is solely for informational purposes. Customers must be aware of the suitability of this product for their application, and consider that variable factors such as Manufacturer, Product Category, Date Codes, Pictures and Descriptions may differ from available inventory.

© 2000 Fairchild Semiconductor Corporation DS006470 www.fairchildsemi.com
August 1986
Revised April 2000
DM74S157 • DM74S158 Quad 1 of 2 Line Data Selector/Multiplexer
DM74S157 DM74S158
Quad 1 of 2 Line Data Selector/Multiplexer
General Description
These data selectors/multiplexers contain inverters and
drivers to supply full on-chip data selection to the four out-
put gates. A separate strobe input is provided. A 4-bit word
is selected from one of two sources and is routed to the
four outputs. The DM74S157 presents true data whereas
the DM74S158 presents inverted data to minimize propa-
gation delay time.
Applications
Expand any data input point
Multiplex dual data buses
Generate four functions of two variables (one variable is
common)
Source programmable counters
Features
Buffered inputs and outputs
Typical propagation time
DM74S157 5 ns
DM74S158 4 ns
Typical power dissipation
DM74S157 250 mW
DM74S158 195 mW
Ordering Code:
Connection Diagrams
DM74S157 DM74S158
Order Number Package Number Package Description
DM74S157N N16E 16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
DM74S158N N16E 16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
www.fairchildsemi.com 2
DM74S157 DM74S158
Function Table
H = HIGH Level
L = LOW Level
X = Don’t Care
Logic Diagrams
DM74S157
DM74S158
Inputs Output Y
Strobe Select A B DM74S157 DM74S158
HXXXLH
LLLXLH
LLHXHL
LHXLLH
LHXHHL
3 www.fairchildsemi.com
DM74S157 DM74S158
Absolute Maximum Ratings(Note 1)
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.
DM74157 Recommended Operating Conditions
DM74S157 Electrical Characteristics
over recommended operating free air temperature (unless otherwise noted)
Note 2: All typicals are at V
CC
= 5V, T
A
= 25°C.
Note 3: Not more than one output should be shorted at a time, and the duration should not exceed one second.
Note 4: I
CC
is measured 4.5V applied to all inputs and all outputs OPEN.
DM74S157 Switching Characteristics
at V
CC
= 5V and T
A
= 25°C
Supply Voltage 7V
Input Voltage 5.5V
Operating Free Air Temperature Range 0°C to +70°C
Storage Temperature Range 65°C to +150°C
Symbol Parameter Min Nom Max Units
V
CC
Supply Voltage 4.75 5 5.25 V
V
IH
HIGH Level Input Voltage 2 V
V
IL
LOW Level Input Voltage 0.8 V
I
OH
HIGH Level Output Current 1mA
I
OL
LOW Level Output Current 20 mA
T
A
Free Air Operating Temperature 0 70 °C
Symbol Parameter Conditions Min
Typ
Max Units
(Note 2)
V
I
Input Clamp Voltage V
CC
= Min, I
I
= 18 mA 1.2 V
V
OH
HIGH Level V
CC
= Min, I
OH
= Max
2.7 3.4 V
Output Voltage V
IL
= Max, V
IH
= Min
V
OL
LOW Level V
CC
= Min, I
OL
= Max
0.5 V
Output Voltage V
IH
= Min, V
IL
= Max
I
I
Input Current @ Max Input Voltage V
CC
= Max, V
I
= 5.5V 1 mA
I
IH
HIGH Level V
CC
= Max S or G 100
µA
Input Current V
I
= 2.7V A or B 50
I
IL
HIGH Level V
CC
= Max S or G 4
mA
Input Current V
I
= 0.5V A or B 2
I
OS
Short Circuit Output Current V
CC
= Max (Note 3) 40 100 mA
I
CC
Supply Current V
CC
= Max (Note 4) 50 78 mA
R
L
= 280
Symbol Parameter From (Input)
C
L
= 15 pF C
L
= 50 pF
Units
To (Output) Min Max Min Max
t
PLH
Propagation Delay Time
Data to Y 7.5 10 ns
LOW-to-HIGH Level Output
t
PHL
Propagation Delay Time
Data to Y 6.5 10 ns
HIGH-to-LOW Level Output
t
PLH
Propagation Delay Time
Strobe to Y 12.5 15 ns
LOW-to-HIGH Level Output
t
PHL
Propagation Delay Time
Strobe to Y 12 15 ns
HIGH-to-LOW Level Output
t
PLH
Propagation Delay Time
Select to Y 15 17 ns
LOW-to-HIGH Level Output
t
PHL
Propagation Delay Time
Select to Y 15 17 ns
HIGH-to-LOW Level Output
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