Patent ID: 8154355
Filing Date: 2012-04-10
Classification: H03B

Abstract:
1. A high-frequency Colpitts circuit for realizing an oscillation at a high frequency, comprising: an oscillation transistor for amplifying an oscillation frequency signal from a crystal oscillator; and a feedback transistor to a base of which a collector of the oscillation transistor is connected; wherein a supply voltage is applied to the collector of the oscillation transistor through a first resistance, one end of first and second capacitors connected in series is connected to a base of the oscillation transistor and the other end of the capacitors is grounded, a point between the first and second capacitors is connected to an emitter of the oscillation transistor, one end of a coil is connected to the emitter, a second resistance and a third capacitor connected in parallel is connected in series to the other end of the coil, the other ends of the parallel connection are grounded, and a resonance circuit is composed of the coil and the second capacitor, and the supply voltage is applied to a collector of the feedback transistor through a third resistance and is connected to an output terminal and the collector is connected to the base of the oscillation transistor through a feedback resistance.