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. 09, 1995
Filed:
Sep. 12, 1994
Janos Kovacs, North Andover, MA (US);
Ronald Kroesen, Harvard, MA (US);
Analog Devices, Inc., Norwood, MA (US);
Abstract
A center frequency controlled phase locked loop system includes a primary phase locked loop having a first voltage controlled oscillator including a first voltage to current converter whose output current drives a first current controlled oscillator to produce the primary clock signal to be locked onto an input signal; a second phase locked loop having a second voltage controlled oscillator including a second voltage to current converter whose output current drives a second current controlled oscillator to produce the synthesized clock signal whose frequency is approximately that of the input signal or integral multiple thereof; and a current copier circuit for copying the output current from the second voltage to current converter and delivering it to the first current controlled oscillator to maintain the center frequency of the first voltage controlled oscillator at approximately the output frequency of the synthesized clock signal.