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. 11, 2005
Filed:
Dec. 31, 2001
Solomon NG, Tai Po, HK;
Wen LI Luo, Shenzhen, CN;
Solomon Ng, Tai Po, HK;
Wen Li Luo, Shenzhen, CN;
Abstract
An audio amplifier device includes a power supply having an output for providing a supply voltage, a voltage divider connected to the output of the power supply for providing a divided supply voltage, and an audio amplifier that further includes a supply voltage rejection circuit. The audio amplifier has a first input for receiving an input audio signal, a second input for receiving the supply voltage, a third input for receiving a supply voltage rejection signal for the supply voltage rejection circuit, and an output for providing an output audio signal. A power-off noise suppression circuit has a first input for receiving the divided supply voltage and an output for providing the supply voltage rejection signal. The power-off noise suppression circuit sets the supply voltage rejection signal equal to the divided supply voltage during power-off of the power supply so that a rate of decrease of the supply voltage is greater than a rate of decrease of the supply voltage rejection signal for reducing noise in the output audio signal during the power-off.