Hitachi F-ZTAT H8/3039 Series Hardware Manual page 505

External Clock: The external clock frequency should be equal to the system clock frequency (ø).
Table 16-3 and figure 16-6 indicate the clock timing.
Table 16-3 Clock Timing
Item Symbol
External clock t
EXr
rise time
External clock t
EXf
fall time
External clock —
input duty (a/t )
cyc
ø clock width —
duty (b/t )
cyc
EXTAL
ø
496
V =
CC
2.7 V to 5.5 V
Min Max
— 10
— 10
30 70
40 60
40 60
a
t
EXr
b
Figure 16-6 External Clock Input Timing
V =
CC
5.0 V ±10%
Min Max Unit
— 5 ns
— 5 ns
30 70 %
40 60 %
40 60 %
t
cyc
t
EXf
t
cyc
Test Conditions
Figure 16-6
ø ≥ 5 MHz
Figure
ø < 5 MHz 16-6
× 0.5
V
CC
× 0.5
V
CC