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CHAPTER 5 CLOCK GENERATOR
User’s Manual U15104EJ2V0UD
5.4 System Clock Oscillator
5.4.1 System clock oscillator
The system clock oscillator oscillates with a crystal resonator (4.5 MHz TYP.) connected to the X1 and X2 pins.
Figure 5-4 shows an external circuit of the system clock oscillator.
Figure 5-4. External Circuit of System Clock Oscillator
Crystal oscillation
Caution When using a system clock oscillator, wire as follows in the area enclosed by the broken
lines in Figure 5-4 to avoid an adverse effect from wiring capacitance.
•
Keep the wiring length as short as possible.
•
Do not cross the wiring with 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 GND. Do not
ground the capacitor to a ground pattern through which a high current flows.
•
Do not fetch signals from the oscillator.
Crystal resonator
IC
X1
X2
Содержание mPD178053
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