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:
Apr. 17, 2001
Filed:
Aug. 10, 1999
Steven P. Young, San Jose, CA (US);
Jane W. Sowards, Fremont, CA (US);
Wilson K. Yee, Pleasanton, CA (US);
Xilinx, Inc., San Jose, CA (US);
Abstract
The invention provides a structure and method of generating a clock enable signal in a programmable logic device (PLD). A first embodiment of the invention comprises a clock enable circuit implemented such that the critical paths have only two levels of logic. In this embodiment, the critical paths are implemented in dedicated logic while other portions of the clock enable circuit are implemented using programmable logic. According to another embodiment of the invention, the clock enable circuit is located near the center of a first edge of the device. A first plurality of output registers are located along the first edge on either side of the clock enable circuit, with additional output registers being located along the two adjacent half-edges. Programmable interconnection points (PIPs) permit a clock enable interconnect line along the first edge to be programmably extended to the additional output registers. In another embodiment, the clock enable circuit is duplicated in two opposite edges of the device.