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. 11, 1998
Filed:
Apr. 09, 1996
Chu-Chiao Yu, Hsinchu, TW;
Winbond Electronics Corporation, Hsinchu, TW;
Abstract
An analog modulator employing .DELTA.-.SIGMA. transformation and comprising timings generator, at least a single operational-amplifier (OP-amplifier) filter of Biquadratic transfer function and saturation detection circuit, is provided. This novel approach solves the stability issue by controlling the switching timings of the single operation-amplifier biquadratic filter in the .DELTA.-.SIGMA. modulator. During normal operation, this high-order .DELTA.-.SIGMA. modulator constructed by the single OP-amplifier biquadratic filter functions a third-order or fourth-order modulator. As unstable condition occurs, via the saturation detection circuit and timings generator, the third-order or the fourth-order modulator functionally converts into and performs as a stable .DELTA.-.SIGMA. modulator of second-order. As a stable condition is restored after a recovery time, via controlling the timing signals, the modulator functionally resumes its normal function of third-order or fourth-order operation which has a high resolution.