UPD30102 Datasheet, PDF (55/701 Pages) NEC – 64/32-bit Microprocessor

CHAPTER 1 INTRODUCTION
Figure 1-10. Examples of Oscillator with Bad Connection
(a) Connection circuit wiring is too long.
(b) There is another signal line crossing.
Note1
Note2 GND
Note1
Note2 GND
(c) A high varying current flows near a signal line.
(d) A current flows over the ground line of the
generator circuit
(The potentials of points A, B, and C change).
VDD
Note1
Large
current
Note2 GND
Note1
Note2 GND
(e) A signal is extracted.
Note2
Note1 GND
A
BC
Notes 1. CLKX2, RTCX2
2. CLKX1, RTCX1
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