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. 13, 2001
Filed:
Nov. 12, 1998
Toshihiko Kawano, Tokushima-ken, JP;
Ryuuji Wakatsuki, Hamamatsu, JP;
Kiyoto Kuroiwa, Hamamatsu, JP;
Yamaha Corporation, Hamamatsu, JP;
Abstract
A D/A conversion apparatus includes a DSP which receives and converts input digital data with different conversion factors, to generate a plurality of digital data having different levels, selects one of the plurality of the generated digital data, depending upon the signal quality of the input digital data, while attenuating the other digital data to be lower than a predetermined noise level. A plurality of D/A converting devices convert the respective generated digital data into corresponding analog signals. A re-converting device converts the level of each of the analog signals into an original level, based on a corresponding one of the conversion factors with which the input digital data is converted by the DSP. An adding device adds the re-converted analog signals. An attenuating device attenuates, in an input stage of the adding device, medium-to-high frequency components of at least one of the analog signals generated by at least one of the D/A converting devices that receives the attenuated digital data, and corresponding to digital data obtained by converting the input digital data with a smaller conversion factor than that of the digital data selected and generated by the DSP.