HD643303x Hitachi, HD643303x Datasheet - Page 424

• Manufacturer Part Number: HD643303x
• Description: Hitachi Microcomputer
• Manufacturer: Hitachi

External Clock: The external clock frequency should be equal to the system clock frequency (ø).
Table 15-3 and figure 15-6 indicate the clock timing.
Table 15-3 Clock Timing
Item
External clock rise
time
External clock fall
time
External clock
input duty (a/t
ø clock duty
(b/t
cyc
EXTAL
ø
)
cyc
)
Symbol
t
t
—
—
EXr
EXf
Figure 15-6 External Clock Input Timing
t
EXr
Min
—
—
30
40
40
V
2.7 V to 5.5 V
CC
a
b
=
Max
10
10
70
60
60
409
t
t
cyc
cyc
V
Min
—
—
30
40
40
CC
t
EXf
= 5.0 V ± 10%
Max
5
5
70
60
60
ns
ns
%
%
Unit Test Conditions
%
Figure 15-16
ø ≥ 5 MHz
ø < 5 MHz
Figure 15-6
V
V
CC
CC
0.5
0.5
Figure
15-6