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DM74LS155 • DM74LS156
Absolute Maximum Ratings(Note 3)
Note 3: 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.
DM74LS155 Recommended Operating Conditions
DM74LS155 Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted)
Note 4: All typicals are at V
CC
= 5V, T
A
= 25° C.
Note 5: Not more than one output should be shorted at a time, and the duration should not exceed one second.
Note 6: I
CC
is measured with all outputs OPEN, A,B, and C1 inputs at 4.5V, and C2, G1, and G2 inputs GROUNDED.
DM74LS155 Switching Characteristics
at V
CC
= 5V and T
A
= 25°C
Supply Voltage 7V
Input Voltage 7V
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
V
OH
HIGH Level Output Current −0.4 mA
I
OL
LOW Level Output Current 8 mA
T
A
Free Air Operating Temperature 0 70 °C
Symbol Parameter Conditions Min
Typ
Max Units
(Note 4)
V
I
Input Clamp Voltage V
CC
= Min, I
I
= −18 mA −1.5 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
0.35 0.5
Output Voltage V
IL
= Max, V
IH
= Min V
I
OL
= 4 mA, V
CC
= Min 0.25 0.4
I
I
Input Current @ Max Input Voltage V
CC
= Max, V
I
= 7V 0.1 mA
I
IH
HIGH Level Input Current V
CC
= Max, V
I
= 2.7V 20 µA
I
IL
LOW Level Input Current V
CC
= Max, V
I
= 0.4V −0.36 mA
I
OS
Short Circuit Output Current V
CC
= Max (Note 5) −20 −100 mA
I
CC
Supply Current V
CC
= Max (Note 6) 6.1 10 mA
From (Input)
R
L
= 2 kΩ
Symbol Parameter
To (Output)
C
L
= 15 pF C
L
= 50 pF Units
Min Max Min Max
t
PLH
Propagation Delay Time A, B, C2, G1
18 22 ns
LOW-to-HIGH Level Output or G2 to Y
t
PHL
Propagation Delay Time A, B, C2, G1
27 35 ns
HIGH-to-LOW Level Output or G2 to Y
t
PLH
Propagation Delay Time A or B
18 24 ns
LOW-to-HIGH Level Output to Y
t
PHL
Propagation Delay Time A or B
27 35 ns
HIGH-to-LOW Level Output to Y
t
PLH
Propagation Delay Time C1
20 24 ns
LOW-to-HIGH Level Output to Y
t
PHL
Propagation Delay Time C1
27 35 ns
HIGH-to-LOW Level Output to Y
