| 摘要 |
PROBLEM TO BE SOLVED: To provide a voltage-controlled oscillator which is small in power consumption and improved in C/N characteristics. SOLUTION: The oscillator includes: a first resonance circuit 10 including a first variable capacitance diode D11 having a cathode connected to a control terminal Ta via a choking inductor L1, a first capacitor and a line S4 (a first inductor) connected between an anode of the first variable capacitance diode and ground; a second resonance circuit 20 including a second variable capacitance diode D12 having a cathode connected to the control terminal via the choking inductor L1, a second capacitor C42 and a second inductor L42 connected between an anode of the second variable capacitance diode and ground; and an oscillation circuit coupled to the first and second resonance circuits and outputting an oscillation output. The first resonance circuit nearly determines a resonance frequency and the second resonance circuit makes adjustments so as to improve the C/N characteristics. COPYRIGHT: (C)2008,JPO&INPIT
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