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:
Feb. 20, 2007
Filed:
Aug. 25, 2005
Thomas Mayer, Linz, AT;
Werner Schelmbauer, Linz, AT;
Günter Märzinger, Ulrichsberg, AT;
Infineon Technologies AG, Munich, DE;
Abstract
The invention includes a phase locked loop which has a voltage-controlled oscillator, a phase comparator and a charge pump. The charge pump is coupled to a setting input of the voltage-controlled oscillator via a loop filter. A feedback input of the phase comparator is connected to the output of the voltage-controlled oscillator via a frequency divider, and the phase comparator is designed to output an actuating signal to the charge pump. The loop filter has a first charge store and at least one tunable element that alters a filter characteristic of the loop filter. In addition, there is a trimming circuit which is coupled to the at least one further element in order to alter the filter characteristic of the loop filter and which is designed to compare a time period for a charging operation in a loop filter with a reference time period.