| 摘要 |
PROBLEM TO BE SOLVED: To provide a colpitts oscillator which controls variation in drive-level that oscillates a piezoelectric oscillator with respect to ambient temperature change. SOLUTION: In the colpitts oscillator, a series circuit which is composed of capacitors C1 and C2 as one part of a load capacitance is connected between a base and a ground of an oscillation transistor TR1, and an emitter of the oscillation transistor TR1 is connected to a connection middle point of the series circuit. In addition, an emitter resistance R1 is connected between the emitter and the ground. Then, a series circuit which is composed of a resistance R2 and a thermistor TH1 is connected in parallel with the emitter resistance R1. A base bias circuit which is composed of resistances R3 and R4 is connected to the base of the oscillation transistor TR1, and a piezoelectric oscillator X1 is connected between the base and the ground of the oscillation transistor TR1. COPYRIGHT: (C)2010,JPO&INPIT
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