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. 29, 2002
Filed:
Sep. 27, 1999
Wei-Chan Hsu, San Jose, CA (US);
Waytech Investment Co., Ltd., Tortola, VG;
Abstract
Invention resides in a switching amplifier having a quaternary input control signal that provides quaternary levels (1, 0H, −1, and 0L) which is coupled to an H-bridge amplifier to provide error cancellation in switching amplifier output signal. The quaternary control signal alternates from a zero state at a high level (“0H”) to a zero state at a low level (“0L”) between each non-zero state (+1 or −1). In a preferred embodiment, a three-level sigma-delta modulator is provided for greater operational efficiency for ease of detecting zero states and minimizing power. The three-level sigma-delta modulator receives and converts an amplifier input signal into a ternary output signal that is then coupled to a ternary-to-quaternary converter to generate the quaternary control signal to provide as input to the H-bridge.