HD6432621 Hitachi, HD6432621 Datasheet - Page 727

• Manufacturer Part Number: HD6432621
• Description: (HD64F262x Series) 16-Bit Microcomputer
• Manufacturer: Hitachi

External Clock: Use an external clock frequency of 20 MHz or less.
Table 20-4 and figure 20-7 show the input conditions for the external clock.
Table 20-4 External Clock Input Conditions
Item
External clock input
low pulse width
External clock input high
pulse width
External clock rise time
External clock fall time
Clock low pulse
width level
Clock high pulse
width level
EXTAL
t
EXr
Figure 20-7 External Clock Input Timing
Symbol
t
t
t
t
t
t
EXL
EXH
EXr
EXf
CL
CH
t
V
PV
Min
15
15
—
—
0.4
80
0.4
80
EXH
CC
CC
= 3.0 V to 3.6 V,
= 5.0 V ±10%
Max
—
—
5
5
0.6
—
0.6
—
t
EXf
t
EXL
Unit
ns
ns
ns
ns
t
ns
t
ns
cyc
cyc
Test Conditions
Figure 20-7
ø
ø < 5 MHz
ø
ø < 5 MHz
5 MHz
5 MHz
V
CC
0.5
Figure 22-2
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