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4
74
V
HC138
AC Electrical Characteristics
Note 3: CPD is defined as the value of the internal equivalent capacitance which is calculated from the operating current consumption without load. Average
operating current can be obtained by the equation: ICC (opr.) = CPD * VCC * fIN + ICC.
Symbol
Parameter
VCC
(V)
TA = 25°CTA = 40°C to +85°C
Units
Conditions
Min
Typ
Max
Min
Max
tPLH
Propagation Delay
3.3
± 0.3
8.2
11.4
1.0
13.5
ns
CL = 15 pF
tPHL
An to On
10.0
15.8
1.0
18.0
CL = 50 pF
5.0
± 0.5
5.7
8.1
1.0
9.5
ns
CL = 15 pF
7.2
10.1
1.0
11.5
CL = 50 pF
tPLH
Propagation Delay
3.3
± 0.3
8.1
12.8
1.0
15.0
ns
CL = 15 pF
tPHL
E3 to On
10.6
16.3
1.0
18.5
CL = 50 pF
5.0
± 0.5
5.6
8.1
1.0
9.5
ns
CL = 15 pF
7.1
10.1
1.0
11.5
CL = 50 pF
tPLH
Propagation Delay
3.3
± 0.3
8.2
11.4
1.0
13.5
ns
CL = 15 pF
tPHL
E1 or E2 to On
10.7
14.9
1.0
17.0
CL = 50 pF
5.0
± 0.5
5.8
8.1
1.0
9.5
ns
CL = 15 pF
7.3
10.1
1.0
11.5
CL = 50 pF
CIN
Input Capacitance
4
10
pF
VCC = Open
CPD
Power Dissipation
34
pF
(Note 3)
Capacitance