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. 17, 2015
Filed:
Sep. 06, 2013
Applicant:
Synopsys, Inc., Mountain View, CA (US);
Inventors:
Skye Wolfer, Hillsboro, OR (US);
David A. Yokoyama-Martin, Portland, OR (US);
Assignee:
Synopsys, Inc., Mountain View, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03K 17/00 (2006.01); H03K 5/125 (2006.01);
U.S. Cl.
CPC ...
H03K 5/125 (2013.01);
Abstract
A digital phase selector circuit that switches an output clock between N input clock phases is described. The phase selector utilizes a special output mux and switches clock phases during a safe zone to avoid glitches. The phase selector is used in the feedback path of a PLL to implement functions such as spread spectrum or fractional reference clocks. An example with N=4 and an optimized latch mux is shown.