Hitachi H8S/2631, Руководство по оборудованию

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848
External Clock
Table 23-4 and figure 23-7 show the input conditions for the external clock.
Table 23-4 External Clock Input Conditions
V
CC
= 3.0 V
to 3.6 V,
PV
CC
= 3.0 V
to 5.5 V
V
CC
= 3.0 V
to 3.6 V
PV
CC
= 5.0 V
±10%
Item Symbol Min Max Min Max Unit Test Conditions
External clock input low
pulse width t
EXL
20 — 15 — ns Figure 23-7
External clock input
high pulse width t
EXH
20 — 15 — ns
External clock rise time t
EXr
— 10 — 5 ns
External clock fall time t
EXf
— 10 — 5 ns
Clock low pulse
width level t
CL
0.4 0.6 0.4 0.6 t
cyc
ø
≥
5 MHz Figure
25-2
80 — 80 — ns ø < 5 MHz
Clock high pulse width
level t
CH
0.4 0.6 0.4 0.6 t
cyc
ø
≥
5 MHz
80 — 80 — ns ø < 5 MHz
t
EXH
t
EXL
t
EXr
t
EXf
V
CC
×
0.5
EXTAL
Figure 23-7 External Clock Input Timing