| 摘要 |
PROBLEM TO BE SOLVED: To suppress the generation of a waveform distortion of an output signal of an LC oscillator.SOLUTION: An LC oscillator has a circuit configuration in which an inductor element of an oscillation circuit and an inductor element of a feedback amplification circuit are inductor-coupled via a mutual inductance, and reduces a signal voltage input into the feedback amplification circuit from the oscillation circuit to reduce a waveform distortion due to a differential configuration of the feedback amplification circuit. A further configuration using capacitive coupling can set independent bias voltages of the oscillation circuit and the feedback amplification circuit, and a feedback amplifier used may either be a single-ended circuit ensuring a wide output voltage range or be a differential circuit robust to element variations, temperature variations and the like. The oscillation circuit is a Colpitts oscillation circuit, and the oscillation circuit can have a central value of an output voltage at a supply voltage to implement a high oscillation output and a high Q value. |
