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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
= 280Ω
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
