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:
May. 15, 2001
Filed:
Jul. 22, 1999
Christopher H. Kingsley, San Jose, CA (US);
Trevor J. Bauer, San Jose, CA (US);
Robert W. Wells, Cupertino, CA (US);
Robert D. Patrie, Scotts Valley, CA (US);
Xilinx, Inc., San Jose, CA (US);
Abstract
A circuit measures a signal propagation delay through a series of memory elements. In one embodiment the memory elements are configured in series so that together they form a delay circuit. In another embodiment the memory elements are configured in a loop to form a ring oscillator. Each memory element propagates a signal to a subsequent memory element so that the time the signal takes to traverse all of the memory elements is proportional to the average delay induced by the individual elements. This proportionality provides an effective means for measuring the delays of those components. Various embodiments of the invention measure the speeds at which memory elements can be preset, cleared, written to, read from, or clock enabled.