摘要 |
There is provided a voltage variable capacitor that can be formed on a semiconductor circuit, has a large variable ratio of capacitances and a high Q value, and achieves a highly linear relation of a control voltage and an oscillation frequency when the capacitor forms a VCO. The voltage variable capacitor is formed of a plurality of MOS capacitance elements (CM1 to CMn) having lower electrodes connected in common, the same number of non-variable capacitors (C1 to Cn) having one ends connected to upper electrodes of the plurality of MOS capacitance elements and the other ends connected in common, and a unit (VB1 to VBn and resistors) applying different fixed bias voltages to connection points of these MOS capacitance elements and non-variable capacitors, in which a control voltage is applied to the lower electrodes connected in common of the plurality of MOS capacitance elements.
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