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. 20, 2001
Filed:
Feb. 15, 2000
Donald H. Friedberg, Breinigsville, PA (US);
Dale Harvey Nelson, Shillington, PA (US);
Lai Q. Pham, Center Valley, PA (US);
Agere Systems Guardian Corp., Orlando, FL (US);
Abstract
A method and lock detector for detecting lock between a reference signal and a feedback signal of a PLL circuit. A number of clock cycles of the feedback signal is counted during consecutive test intervals defined by the reference signal. A feedback comparator determines whether the number of clock cycles of the feedback signal during a given test interval is within an expected range. Before lock has been indicated, a qualification counter is either incremented or reset after each test interval in accordance with the expected range determination. A lock indication signal indicating that lock has been achieved is provided if said qualification counter exceeds a qualification threshold.