Datasheet

CHAPTER 27 ELECTRICAL SPECIFICATIONS (STANDARD PRODUCTS)
User’s Manual U18698EJ1V0UD
544
Standard
p
roducts
Internal Oscillator Characteristics
(TA = −40 to +85°C, 1.8 V ≤ VDD ≤ 5.5 V, VSS = AVSS = 0 V)
Resonator Parameter Conditions MIN. TYP. MAX. Unit
2.5 V ≤ VDD ≤ 5.5 V 7.6 8.0 8.4 MHz RSTS = 1
1.8 V ≤ V
DD < 2.5 V 6.75 8.0 8.4 MHz
8 MHz internal
oscillator
Internal high-speed oscillation
clock frequency (f
RH)
Notes 1, 2
RSTS = 0 2.48 5.6 9.86 MHz
2.6 V ≤ VDD ≤ 5.5 V 216 240 264 kHz 240 kHz internal
oscillator
Internal low-speed oscillation
clock frequency (f
RL)
1.8 V ≤ V
DD < 2.6 V 192 240 264 kHz
Notes 1. Indicates only oscillator characteristics. Refer to AC Characteristics for instruction execution time.
2. When setting HIOTRM = 10H (±0%: default)
Remark RSTS: Bit 7 of the internal oscillation mode register (RCM)
XT1 Oscillator Characteristics
(T
A = −40 to +85°C, 1.8 V ≤ VDD ≤ 5.5 V, VSS = AVSS = 0 V)
Resonator Recommended Circuit Parameter Conditions MIN. TYP. MAX. Unit
Crystal
resonator
XT1XT2
C4
C3
Rd
VSS
XT1 clock oscillation
frequency (f
XT)
Note
32 32.768 35 kHz
Note Indicates only oscillator characteristics. Refer to AC Characteristics for instruction execution time.
Cautions 1. When using the XT1 oscillator, wire as follows in the area enclosed by the broken lines in the
above figure 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 signal line through which a high fluctuating current flows.
• Always make the ground point of the oscillator capacitor the same potential as V
SS.
• Do not ground the capacitor to a ground pattern through which a high current flows.
• Do not fetch signals from the oscillator.
2. The XT1 oscillator is designed as a low-amplitude circuit for reducing power consumption, and
is more prone to malfunction due to noise than the X1 oscillator. Particular care is therefore
required with the wiring method when the XT1 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.