upd78f0124hgba1-8et-a Renesas Electronics Corporation., upd78f0124hgba1-8et-a Datasheet - Page 105

• Manufacturer Part Number: upd78f0124hgba1-8et-a
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

Caution When using the high-speed system clock oscillator and subsystem clock oscillator, wire as
Remark When using the subsystem clock, replace X1 and X2 with XT1 and XT2, respectively. Also, insert
Figure 5-10 shows examples of incorrect resonator connection.
follows in the area enclosed by the broken lines in the Figures 5-8 and 5-9 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 fetch signals from the oscillator.
Note that the subsystem clock oscillator is designed as a low-amplitude circuit for reducing
power consumption.
resistors in series on the XT2 side.
ground the capacitor to a ground pattern through which a high current flows.
(a) Too long wiring
V
Figure 5-10. Examples of Incorrect Resonator Connection (1/2)
SS
X1
CHAPTER 5 CLOCK GENERATOR
X2
User’s Manual U16962EJ3V0UD
V
SS
(b) Crossed signal line
X1
PORT
X2
SS
. Do not
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