AC Electrical Characteristics
54AC
=
VCC
(V)
TA −55˚C
Fig.
No.
Symbol
Parameter
to +125˚C
Units
=
CL 50 pF
(Note 8)
Min
Max
fmax
tPLH
tPHL
tPLH
tPHL
tPLH
tPHL
tPHL
tPHL
Maximum Count
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
55
80
MHz
ns
Frequency
Propagation Delay CP to Qn
(PE Input HIGH or LOW)
Propagation Delay CP to Qn
(PE Input HIGH or LOW)
Propagation Delay
CP to TC
1.0
1.0
1.0
1.0
3.0
3.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
14.0
10.0
14.0
10.0
18.0
13.0
17.5
13.0
13.0
8.5
ns
ns
Propagation Delay
CP to TC
ns
Propagation Delay
CET to TC
ns
Propagation Delay
CET to TC
13.5
10.5
14.5
10.5
18.5
14.0
ns
Propagation Delay
MR to Qn
ns
Propagation Delay
MR to TC
ns
±
Note 8: Voltage Range 3.3 is 3.3V 0.3V
±
Range 5.0 is 5.0V 0.5V
AC Operating Requirements
54AC
=
VCC
TA −55˚C
Fig.
No.
Symbol
Parameter
(V)
to +125˚C
Units
=
CL 50 pF
(Note 9)
Guaranteed Minimum
ts
Setup Time, HIGH or LOW
Pn to CP
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
16.0
10.5
0.5
ns
ns
ns
ns
ns
ns
ns
ns
ns
th
ts
Hold Time, HIGH or LOW
Pn to CP
1.5
Setup Time, HIGH or LOW
PE to CP
15.0
10.5
−1.0
0.0
th
ts
Hold Time, HIGH or LOW
PE to CP
Setup Time, HIGH or LOW
CEP or CET to CP
Hold Time, HIGH or LOW
CEP or CET to CP
Clock Pulse Width
(Load) HIGH or LOW
Clock Pulse Width
(Count) HIGH or LOW
MR Pulse Width,
7.5
5.5
th
tw
tw
tw
2.0
2.0
5.0
5.0
5.0
5.0
5.0
LOW
5.0
7
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