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:
May. 29, 2012
Filed:
Aug. 28, 2007
Ryota Homma, Kanagawa, JP;
Koji Kudo, Kanagawa, JP;
Ryota Homma, Kanagawa, JP;
Koji Kudo, Kanagawa, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A digital amplifier amplifies an input signal from a tuner () which receives a broadcast wave of a set receiving frequency so as to suppress degradation of the high-band reproduction performance and lowering of the amplification efficiency. The digital amplifier includes: a band division unit () for dividing an input signal into a plurality of bands; a high-band pulse width modulation unit () and a low-band pulse width modulation unit () which modulate the input signal of the respective bands divided by the band division unit (), by the pulse width modulation method; a switching frequency control unit () which obtains a receiving frequency in the tuner () and controls a switching frequency (fsa) in the high-band pulse width modulation unit () and a switching frequency (fsb) in the low-band pulse width modulation unit (); and a high-band amplification unit () and a low-band amplification unit () which amplify the input signal which has been subjected to pulse width modulation by the high-band pulse width modulation unit () and the low-band pulse width modulation unit ().