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:
Nov. 09, 1999
Filed:
Nov. 17, 1997
See-Hoi Caesar Wong, Fremont, CA (US);
Edward Liu, Sunnyvale, CA (US);
LSI Logic Corporation, Milpitas, CA (US);
Abstract
A novel signal processing scheme comprises a digital to analog converter which is clocked at a first frequency, and a switched capacitor filter which receives input from the digital to analog converter and is clocked at a second frequency which is a multiple N times the first frequency. A preferred version of the present invention further comprises an analog signal sychronization circuit which allows the switched capacitor filter to oversample output from the digital to analog converter. The analog signal sychronization circuit comprises a sample and hold circuit, which receives input from the digital to analog converter and holds the input so that the switched capacitor filter can sample the same input N times, and a digital clock generator, which clocks the sample and hold circuit such that the sample and hold circuit only samples settled and valid output data from the digital to analog converter. An RC active filter receives input from the switched capacitor filter and rejects signal images at the first and higher frequencies.