UPD78F0838 Renesas Electronics Corporation., UPD78F0838 Datasheet - Page 856

• Manufacturer Part Number: UPD78F0838
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

29.2 Oscillator Characteristics
(1) Main System Clock (Crystal/Ceramic) Oscillator Characteristics
Note Indicates only oscillator characteristics. Refer to AC Characteristics for instruction execution time.
Cautions 1. When using the X1 oscillator, wire as follows in the area enclosed by the broken lines in the
Remark For the resonator selection and oscillator constant, customers are requested to either evaluate the
854
Ceramic
resonator
Crystal
resonator
Resonator Recommended Circuit
(T
V
A
SS
=
= EV
2. Since the CPU is started by the 8 MHz internal oscillator after reset, check the oscillation
oscillation themselves or apply to the resonator manufacturer for evaluation.
40 to +85 C, 2.7 V
SS
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 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.
stabilization time of the main system clock using the oscillation stabilization time counter status
register (OSTC). Determine the oscillation stabilization time of the OSTC register and oscillation
stabilization time select register (OSTS) after sufficiently evaluating the oscillation stabilization
time with the resonator to be used.
V
V
= AV
SS
SS
C1
C1
CHAPTER 29 ELECTRICAL SPECIFICATIONS ((A) GRADE PRODUCTS) (TARGET)
X1
X1
SS
C2
C2
= SMV
X2
X2
SS
X1 clock
oscillation
frequency (f
X1 clock
oscillation
frequency (f
= 0 V)
Parameter
V
DD
Preliminary User’s Manual U19748EJ1V0UD
= EV
X
X
)
)
Note
Note
DD
4.0 V
2.7 V
4.0 V
2.7 V
5.5 V, 2.7 V
V
V
V
V
DD
DD
DD
DD
< 4.0 V
< 4.0 V
5.5 V
5.5 V
Conditions
AV
REF
5.5 V, 2.7 V
MIN.
4.0
4.0
4.0
4.0
TYP.
SMV
SS
MAX.
.
DD
20
10
20
10
5.5 V,
MHz
MHz
Unit