Oscillation device and mobile communication apparatus
AssigneeMatsushita Electric Industrial Co., Ltd.
InventorsKaoru Ishida, Toshiakira Ando
Life of this patent
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Abstract
A differential type voltage control oscillator is formed of a differential tank circuit, an oscillation transistor, and a differential variable capacitance circuit. The differential variable capacitance circuit has a configuration wherein at least one pair of varactor diodes are connected in an anti-parallel manner, and are separated by means of a plurality of capacitors in a direct current manner. In addition, a differential control voltage is generated by a charge pump circuit which is controlled by the output of a phase comparator, and the differential control voltage is directly applied across the anodes and the cathodes of the varactor diodes.
Claims18
An oscillation device, comprising:
- a differential type voltage control oscillator that includes a differential variable capacitance circuit of which the differential capacitance varies in accordance with a differential control voltage;
- and a control circuit for supplying said differential control voltage to said differential variable capacitance circuit, wherein
- said differential variable capacitance circuit is formed of at least one pair of varactor diodes which are connected to each other in an anti-parallel manner, and of a group of capacitors for separating direct currents flowing through said varactor diodes, and
- said differential control voltage of said control circuit is respectively applied to the cathodes and the anodes of said varactor diodes.
A mobile communication apparatus with an oscillation device, wherein said oscillation device comprises:
- a differential type voltage control oscillator that includes a differential variable capacitance circuit of which the differential capacitance varies in accordance with a differential control voltage;
- and a control circuit for supplying said differential control voltage to said differential variable capacitance circuit, wherein
- said differential variable capacitance circuit is formed of at least one pair of varactor diodes which are connected to each other in an anti-parallel manner, and of a group of capacitors for separating direct currents flowing through said varactor diodes, and
- said differential control voltage of said control circuit is respectively applied to the cathodes and the anodes of said varactor diodes.
Dependencies are inferred from the claim text.