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:
Aug. 02, 2011
Filed:
May. 31, 2007
Cheng-hsuan Fan, Hsinchu, TW;
Chao-hsuan Chuang, Chupei, TW;
Hung-che Chou, Jiadong Township, Pingtung County, TW;
Ching-hsiang Yang, Taoyuan, TW;
Shui-mu Lin, Taichung, TW;
Chih-ping Tan, Hsinchu, TW;
Cheng-Hsuan Fan, Hsinchu, TW;
Chao-Hsuan Chuang, Chupei, TW;
Hung-Che Chou, Jiadong Township, Pingtung County, TW;
Ching-Hsiang Yang, Taoyuan, TW;
Shui-Mu Lin, Taichung, TW;
Chih-Ping Tan, Hsinchu, TW;
Richtek Technology Corporation, Hsin-Chu, TW;
Abstract
The present invention discloses a half-voltage headphone driver circuit, comprising: at least one operational amplifier providing an output to a headphone speaker, and a charge pump receiving a supply voltage (VDD), generating a positive half-voltage and a negative half-voltage (VDD/2 and −VDD/2) based on the supply voltage, and supplying the positive half-voltage and negative half-voltage as high and low operation levels to the at least one operational amplifier.