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:
Mar. 28, 2000
Filed:
Sep. 01, 1998
James A Bailey, Snowflake, AZ (US);
Angelo R Mastrocola, West Lawn, PA (US);
Jeffrey L Sonntag, Allentown, PA (US);
William B Wilson, Macungie, PA (US);
Lucent Technologies Inc., Murray Hill, NJ (US);
Abstract
A phase-locked loop (PLL) has a master circuit configured to a slave circuit. The slave circuit has a phase detector, a charge pump, a loop filter, and a voltage-controlled oscillator configured to operate as a closed-loop PLL. The master circuit has a phase detector and a charge pump that are similar to the corresponding components in the slave circuit. The master circuit is configured to receive two input signals with zero phase offset. As such, any net current charge generated by the master charge pump will be indicative of mismatch within the master phase detector and charge pump, and therefore, by analogy, indicative of mismatch within the slave phase detector and charge pump, as well. A voltage signal generated by the master circuit is applied to control the generation of currents by the slave charge pump in such a way as to compensate for static phase offset that would otherwise exist in the slave circuit.