The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 09, 2007
Filed:
Jan. 27, 2006
Junichi Matsuura, Inagi, JP;
Junichi Matsuura, Inagi, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
With a variable capacitor including a load capacitor of an oscillation circuit having a feedback resistor, an inverter, and a crystal oscillator, and a static capacitance generated between a drain terminal and a gate terminal of MOS transistorsand, in which source and backgate terminals are shorted to each other, a serial connection of a DC cut capacitorand a variable capacitors (MOS transistor)andis formed between one end and the other end of the crystal oscillator. For example, a threshold voltage control signal of the MOS transistorsandis input to the drain terminal through a high-frequency elimination resistor, and is input to the source-backgate terminal through a high-frequency elimination resistor. In addition, a signal obtained by overlapping a temperature characteristic compensation signal and a threshold voltage control signal of the MOS transistoris input to the gate terminal. Accordingly, it is possible to indiscriminately determine an output bias of a temperature compensation control circuit or an external voltage frequency control circuit.