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:
Mar. 24, 2020
Filed:
Jul. 03, 2018
Panasonic Intellectual Property Management Co., Ltd., Osaka, JP;
Shinichi Watanabe, Osaka, JP;
Abstract
A digital amplifier includes a digital PWM generator, a first amplifier circuit, a first low-pass filter, a second amplifier circuit, a second low-pass filter, an attenuator, an error extractor, an adder, and a voltage supply unit. The first amplifier circuit amplifies a digital PWM signal at a second voltage. The first low-pass filter extracts a low-frequency band voltage signal from the amplified digital PWM signal, and outputs the extracted voltage signal to a load. The second amplifier circuit amplifies the generated digital PWM signal at a third voltage. The error extractor extracts an error signal. The adder adds a digital error signal whose feedback gain is adjusted to a digital audio signal. The voltage supply unit generates the third voltage that has a voltage value of a predetermined ratio to a voltage value of the second voltage, and supplies the third voltage to the second amplifier circuit.