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CHAPTER 25 ELECTRICAL SPECIFICATIONS
User’s Manual U15798EJ2V0UD
Subsystem 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
Crystal
Oscillation
V
DD
= 1.8 to 5.5 V
32
32.768
35
kHz
resonator
frequency (f
XT
)
Note 1
Oscillation
V
DD
= 4.5 to 5.5 V
1.2
2
s
stabilization time
Note 2
V
DD
= 1.8 to 5.5 V
10
s
External
XT1 input frequency (f
XT
)
Note 1
32
35
kHz
clock
XT1 input high-/low-level width (t
XTH
, t
XTL
)
5
15
µ
s
Notes 1.
Indicates only oscillator characteristics.
2.
Time required to stabilize oscillation after reset or STOP mode release.
Cautions 1. When using the subsystem 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. The subsystem clock oscillator is designed as a low-amplitude circuit for reducing current
consumption, and is more prone to malfunction due to noise than the main system clock
oscillator. Particular care is therefore required with the wiring method when the subsystem
clock is used.
Remark
For the resonator selection and oscillator constant, customers are requested to either evaluate the
oscillation themselves or apply to the resonator manufacturer for evaluation.
Capacitance (T
A
= 25
°
C, V
DD
= V
SS
= 0 V)
Parameter
Symbol
Conditions
MIN.
TYP.
MAX.
Unit
Input
C
IN
f = 1 MHz
15
pF
capacitance
Unmeasured pins returned to 0 V.
I/O
C
IO
f = 1 MHz
P00 to P07, P20 to P27, P32 to
15
pF
capacitance
Unmeasured pins
P35, P40 to P43, P80 to P87,
returned to 0 V.
P90 to P97, P100 to P107, P110
to P113
P30, P31, P70 to P73
20
pF
Remark
Unless specified otherwise, the characteristics of alternate-function pins are the same as those of port
pins.
C4
XT2
XT1
R
C3
V
SS1
XT1
XT2
