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:
Feb. 25, 1997
Filed:
Aug. 07, 1995
David Yatim, Austin, TX (US);
James W Girardeau, Jr, Austin, TX (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A D/A converter (10) converts a digitized analog signal (32) to an analog signal (50). The D/A converter (10) includes first filtering stage (12), second filtering stage (14), and reduced-bit D/A converter (16). The first filtering stage (12) operates at a first sampling rate (25), interpolates the digitized analog signal (32) from an initial sampling rate to a first sampling rate (25), performs an anti-alias filter, and performs a first comb filtering function. The second filtering stage (14) operates at a second sampling rate (46), interpolates the digitized analog signal (32) to the second sampling rate (46), performs a second comb filtering function, and performs a noise shaper filter to produce a reduced-bit second sampling rate signal (48). The reduced-bit D/A converter (16) converts the second sampling rate signal (48) to an analog signal (50).