摘要 |
A transfer impedance from input terminals of a resonator to output terminals of the resonator is larger than a driving-point impedance of the input terminals of the resonator at an oscillation frequency. The input terminals of the resonator are connected with the drain terminals of transistors Q1 and Q2 that are outputs of a differential amplifier, and the output terminals of the resonator are connected with gate terminals of the transistors Q1 and Q2 that are inputs of the differential amplifier. With this configuration, during the oscillating operation, the oscillation voltage amplitude of the gate terminals of the transistors Q1 and Q2 becomes larger than the oscillation voltage amplitude of the drain terminals. Therefore, it is possible to prevent the transistor, which is oscillating, from operating in a triode region, and suppress the deterioration of the Q-factor. |