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. 10, 1993
Filed:
Mar. 30, 1992
Dhirajlal N Manvar, Austin, TX (US);
Robert C Ledzius, Austin, TX (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A digital-to-analog converter (20) includes a linear interpolator (24) and a converter (25, 26) such as a sigma-delta modulator (25) and an associated analog summing network (26). The linear interpolator (24) includes a differentiator (200), an integrator (202), and a multiplexer (201). The differentiator (200) differentiates a received signal at a first rate. The multiplexer (201) multiplexes an output of the differentiator (200) to provide a multiplexed signal having a larger number of bits than the received signal in order to support multiple interpolating ratios. The integrator (202) integrates the multiplexed signal at a second rate to present to the converter (25, 26). By connecting the multiplexer (201) between the differentiator (200) and the integrator (202), the digital-to-analog converter (20) minimizes the size of the linear interpolator (24) while relieving a critical path between the linear interpolator (24) and the converter (25, 26).