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CHAPTER 24 ELECTRICAL SPECIFICATIONS
User’s Manual U14701EJ3V0UD
Main system clock oscillator characteristics (T
A
= –40 to +85
°
C, V
DD
= 1.8 to 5.5 V)
Resonator
Recommended Circuit
Parameter
Conditions
MIN.
TYP.
MAX.
Unit
Ceramic
resonator
Oscillation
frequency (f
X
)
Note 1
1.0
10
MHz
Oscillation
stabilization time
Note 2
After V
DD
reaches oscil-
lation voltage range MIN.
4
ms
Crystal
resonator
Oscillation
frequency (f
X
)
Note 1
1.0
10
MHz
Oscillation
stabilization time
Note 2
V
DD
= 4.5 to 5.5 V
10
ms
V
DD
= 1.8 to 5.5 V
30
ms
External
clock
X1 input
frequency (f
X
)
Note 1
V
DD
= 4.5 to 5.5 V
1.0
10
MHz
V
DD
= 1.8 to 5.5 V
5.0
MHz
X1 input
high-/low-level width
(t
XH
, t
XL
)
V
DD
= 4.5 to 5.5 V
42.5
500
ns
V
DD
= 1.8 to 5.5 V
85
500
ns
Notes 1.
Indicates only oscillator characteristics.
2.
Time required to stabilize oscillation after reset or STOP mode release.
Cautions 1. When using the main system clock oscillator, wire as follows in the area enclosed by the
broken lines in the above figures to avoid an adverse effect from wiring capacitance.
Keep the wiring length as short as possible.
Do not cross the wiring with the other signal lines.
Do not route the wiring near a line through which a high fluctuating current flows.
Always make the ground point of the oscillator capacitor the same potential as V
SS1
.
Do not ground the capacitor to a ground pattern through which a high current flows.
Do not fetch signals from the oscillator.
2. When the main system clock is stopped and the system is operated by the subsystem clock,
the subsystem clock should be switched again to the main system clock after the oscillation
stabilization time is secured by the program.
C2
X1
X2 IC
C1
C2
X1
X2 IC
C1
X2
X1