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:
Jul. 19, 2005
Filed:
Aug. 27, 2003
Shinichi Ogita, Yawata, JP;
Mitsuhiko Otani, Amagasaki, JP;
Shinichi Ogita, Yawata, JP;
Mitsuhiko Otani, Amagasaki, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A linear-in-dB variable gain amplifier is provided, which approximates gain control characteristics to approximate Linear-in-dB characteristics. A gain G is determined so as to have approximate Linear-in-dB characteristics passing through the maximum value, minimum value, and intermediate value of the gain by a capacitance ratio between capacitance of a higher order capacitor string composed of n capacitors or a lower order capacitor string composed of m capacitors selectively connected in parallel to an input fixed capacitor, and capacitance of a lower order capacitor string, a first correction capacitor string composed of n capacitors, or a second correction capacitor string composed of m capacitors selectively connected in parallel to a feedback loop fixed capacitor, in accordance with a gain control signal (Code) of lower order m bits and higher order n bits.