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:
Apr. 30, 2002
Filed:
Jul. 11, 2000
Hiroki Noumi, Fukushima-ken, JP;
Toshiki Baba, Fukushima-ken, JP;
Alps Electric Co., Ltd., Tokyo, JP;
Abstract
The frequency-characteristic switchable buffer circuit includes an amplifying stage, a parallel resonance circuit which serves as an output load of the amplifying stage, a frequency trap circuit electrically connected between the input of the amplifying stage and a reference potential point, and a frequency switching voltage generator for selectively generating a first switching voltage or a second switching voltage. The parallel resonance circuit parallel-resonates at a first frequency when the first switching voltage is supplied thereto. When the second switching voltage is supplied thereto, the parallel resonance circuit parallel-resonates at a second frequency. The frequency trap circuit comprises a series circuit made up of a diode and a capacitor. When the first switching voltage is supplied to the frequency trap circuit, the frequency trap circuit series-resonates at a frequency lower than the first frequency. When the second switching voltage is supplied thereto, it series-resonates at any of frequencies lying within a 1700 MHz band, which is higher than the second frequency.