| 摘要 |
A voltage controlled oscillator is provided to obtain a high phase noise characteristic and reduce current consumption. A voltage control oscillator includes a resonator(210), a first transistor(221), a second transistor(222), a first power source(241), a second power source(242), first and second capacitor banks(231,232), and first and second feedback capacitors(251,252). The resonator resonates in a frequency determined by the capacitance and the inductance varied according to the control voltage. The first transistor includes the first to third electrodes and the first electrode is connected to the resonator. The second transistor includes the first to third electrodes and the first electrode is connected to the resonator. The first and second power sources are connected between the respective third electrode of the first and second transistors and the ground and control the Q value of the resonator. The first and second capacitor banks include a plurality of capacitors connected between the second electrode of the first and second transistors and the third electrode in parallel and a plurality of switches controlling the on and off of respective capacitors. The first and second feedback capacitors are connected in parallel to the first and second power sources. The first electrode of the first transistor is connected to the second electrode of the second transistor. The second electrode of the first transistor is connected to the first electrode of the second transistor. |
