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. 24, 1998
Filed:
May. 12, 1997
Thomas A Knotts, Palo Alto, CA (US);
Cheryl Stout, Fremont, CA (US);
Richard C Walker, Palo Alto, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
An interleaved, tunable ring oscillator is disclosed that produces more output phases without resorting to interpolation. The oscillator is inherently symmetrical and suffers from none of the systematic time errors of an interpolator approach. The oscillator stages are interconnected to allow the oscillating frequency to be higher than the conventional limit of 1/(2*N*T.sub.D). Frequency tuning is accomplished by electronically varying the delay of each stage of the ring oscillator. A mixer cell performs a weighted sum of a first input and a second delayed input. The delay ranges from the delay of the mixer itself to the sum of the delays of the mixer and the delay cell.