| 摘要 |
PURPOSE:To reduce the difference in potential from the wiring of an oscillation system and to obtain the same effect with an improvement in moisture resistance (leak resistance) by surrounding the wiring parts of elements arranged on the circuit board in the oscillator with a power source earth or a potential which is closer to the center level of an oscillation waveform than the power source earth. CONSTITUTION:A crystal oscillators 2 and an IC 3 as components of an oscillation circuit are packaged on the circuit board 1. Two legs of the crystal oscillator are connected to the amplifying circuit 5 in the IC through printed wiring 4 and the operating power source of the amplifier 6 in the amplifying circuit 5 is at a low constant voltage Vreg. Further, 7 is the molding agent of the IC. Printed wiring 8 is the power source earth of this invention and printed wiring 9 and the oscillation system wiring 4 are separated from each other. Consequently, a leak current from the oscillation system wiring all flows in the power source earth 8 and the potential difference between them is less than when other wiring is connected to the Vss, so the flowing leak current is also reduced. Therefore, a current absorbed from the oscillation circuit becomes small, so oscillations are stabilized.
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