upd78f0124m6gba1-8et Renesas Electronics Corporation., upd78f0124m6gba1-8et Datasheet - Page 446

• Manufacturer Part Number: upd78f0124m6gba1-8et
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

Internal Oscillator Characteristics
(T
Subsystem Clock Oscillator Characteristics
(T
Note Indicates only oscillator characteristics. Refer to AC Characteristics for instruction execution time.
Cautions 1. When using the subsystem clock oscillator, wire as follows in the area enclosed by the broken
Remark For the resonator selection and oscillator constant, users are required to either evaluate the oscillation
446
Internal oscillator
Crystal
resonator
External clock
A
A
CHAPTER 28 ELECTRICAL SPECIFICATIONS (STANDARD PRODUCTS, (A) GRADE PRODUCTS) (CONVENTIONAL PRODUCTS)
Resonator
= −40 to +85°C, 2.7 V ≤ V
= −40 to +85°C, 2.7 V ≤ V
2. The subsystem clock oscillator is designed as a low-amplitude circuit for reducing power
themselves or apply to the resonator manufacturer for evaluation.
Resonator
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
• Do not ground the capacitor to a ground pattern through which a high current flows.
• Do not fetch signals from the oscillator.
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 subsystem clock is used.
Recommended Circuit
V
XT2
SS
C4
Rd
XT2
C3
DD
DD
XT1
XT1
Oscillation frequency (f
= EV
= EV
DD
DD
Oscillation frequency
(f
XT1 input frequency
(f
XT1 input high-/low-level
width (t
≤ 5.5 V, 2.7 V ≤ AV
≤ 5.5 V, 2.7 V ≤ AV
Parameter
XT
XT
)
)
Note
Note
User’s Manual U16315EJ3V1UD
Parameter
XTH
, t
XTL
R
)
)
REF
REF
≤ V
≤ V
DD
DD
Conditions
, V
, V
Conditions
SS
SS
= EV
= EV
SS
SS
= AV
= AV
SS
SS
MIN.
MIN.
120
= 0 V)
= 0 V)
32
32
12
32.768
TYP.
TYP.
240
SS
MAX.
MAX.
38.5
480
35
15
.
Unit
Unit
kHz
kHz
kHz
µ
s