| 摘要 |
PROBLEM TO BE SOLVED: To provide a voltage-controlled oscillator which is independent of a temperature compensation control signal and an external voltage frequency control signal, controls a threshold voltage of a MOS transistor, secures a linearity without reducing a variable range of the frequency, and is miniaturized. SOLUTION: An amplifier, a piezoelectric vibrator, and a load capacity 1 and a load capacity 2 between both terminals of the piezoelectric vibrator are provided. The capacity provided as the load capacity 1 is comprised of a variable capacity having a small capacity value change to an input voltage, and the capacity provided as the load capacity 2 is comprised of the variable capacity having a big capacity value change to the input voltage. A signal superposing the temperature compensation control signal and the external voltage frequency control signal is input in control terrminals of the load capacities 1 and 2 through a high-frequency eliminating resistance. An output bias of a temperature compensation control circuit and an external voltage frequency control circuit is freely decided thereby. COPYRIGHT: (C)2007,JPO&INPIT
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