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DM74LS155 • DM74LS156
DM74LS156 Recommended Operating Conditions
DM74LS156 Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted)
Note 7: All typicals are at V
CC
= 5V, T
A
= 25° C.
Note 8: I
CC
is measured with all outputs OPEN, A, B, and C1 inputs at 4.5V, and C2, G1, and G2 GROUNDED.
DM74LS156 Switching Characteristics
at V
CC
= 5V and T
A
= 25°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 Voltage 5.5 V
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 7)
V
I
Input Clamp Voltage V
CC
= Min, I
I
= −18 mA −1.5 V
I
CEX
HIGH Level V
CC
= Min, V
O
= 5.5V
100 µA
Output Current 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
CC
Supply Current V
CC
= Max (Note 8) 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
28 53 ns
LOW-to-HIGH Level Output or G2 to Y
t
PHL
Propagation Delay Time A, B, C2, G1
33 43 ns
HIGH-to-LOW Level Output or G2 to Y
t
PLH
Propagation Delay Time A or B
28 53 ns
LOW-to-HIGH Level Output to Y
t
PHL
Propagation Delay Time A or B
33 43 ns
HIGH-to-LOW Level Output to Y
t
PLH
Propagation Delay Time C1
28 53 ns
LOW-to-HIGH Level Output to Y
t
PHL
Propagation Delay Time C1
34 43 ns
HIGH-to-LOW Level Output to Y
