µ
PD754144, 754244
57
Data Sheet U10040EJ2V1DS
•
µ
PD754244
System Clock Oscillator Characteristics (T
A
= –40 to +85
°
C, V
DD
= 1.8 to 6.0 V)
Resonator
Recommended Constant
Parameter
Testing Conditions
MIN.
TYP.
MAX.
Unit
Ceramic
Oscillation
1.0
6.0
Notes2, 3, 4
MHz
resonator
frequency (f
X
)
Note1
Oscillation
After V
DD
reaches MIN.
4
ms
stabilization
value of oscillation
time
Note 5
voltage range
Crystal
Oscillation
1.0
6.0
Notes2, 3, 4
MHz
resonator
frequency(f
X
)
Note1
Oscillation
V
DD
= 4.5 to 6.0 V
10
ms
stabilization time
Note3
30
ms
External
X1 input
1.0
6.0
Notes2, 3, 4
MHz
clock
frequency (f
X
)
Note1
X1 input high- and
83.3
500
ns
low-level widths
(t
XH
, t
XL
)
Notes 1.
Only the oscillator characteristics are shown. For the instruction execution time, refer to
AC Charac-
teristics
.
2.
If the oscillation frequency is 2.1 MHz < f
X
≤
4.19 MHz at 1.8 V
≤
V
DD
< 2.0 V, set the processor control
register (PCC) to a value other than 0011. If the PCC is set to 0011, the rated machine cycle time
of 1.9
µ
s is not satisfied.
3.
If the oscillation frequency is 4.19 MHz < f
X
≤
6.0 MHz at 1.8 V
≤
V
DD
< 2.0 V, set the processor control
register (PCC) to a value other than 0011 or 0010. If the PCC is set to 0011 or 0010, the rated machine
cycle time of 1.9
µ
s is not satisfied.
4.
If the oscillation frequency is 4.19 MHz < f
X
≤
6.0 MHz at 2.0 V
≤
V
DD
< 2.7 V, set the processor control
register (PCC) to a value other than 0011. If the PCC is set to 0011, the rated machine cycle time of
0.95
µ
s is not satisfied.
5.
Oscillation stabilization time is a time required for oscillation to stabilize after application of V
DD
,
or after the STOP mode has been released.
Caution When using the oscillation circuit of the system clock, wire the portion enclosed in dotted lines
in the figures as follows to avoid adverse influences on the wiring capacitance:
• Keep the wire length as short as possible.
• Do not cross other signal lines.
• Do not route the wiring in the vicinity of lines though which a high fluctuating current flows.
• Always keep the ground point of the capacitor of the oscillation circuit as the same potential
as V
SS
.
• Do not connect the power source pattern through which a high current flows.
• Do not extract signals from the oscillation circuit.
X1
X2
X1
X2
C1
C2
X1
X2
C1
C2
*