UPD784031 Datasheet, PDF (29/90 Pages) NEC – 16/8-BIT SINGLE-CHIP MICROCONTROLLER

Figure 8-3. Examples of Using Oscillator
(1) Crystal/ceramic oscillation
µ PD784031
VSS1
X1
X2
µPD784031
• When EXTC bit of OSTS = 1
(2) External clock
• When EXTC bit of OSTS = 0
µ PD784031
X1
µ PD784031
X1
X2
µPD74HC04, etc.
Open
X2
Caution When using the clock generator, to avoid problems caused by influences such as stray
capacitance, run all wiring within the area indicated by the dotted lines according to the following
rules:
• Minimize the wiring length.
• Wires must never cross other signal lines.
• Wires must never run near a line carrying a large varying current.
• The grounding point of the capacitor of the oscillator circuit must always be at the same
potential as VSS1. Never connect the capacitor to a ground pattern carrying a large current.
• Never extract a signal from the oscillator circuit.
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