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:
Jun. 04, 2013
Filed:
Jan. 08, 2011
Tatsunori Usugi, Hamura, JP;
Takeshi Isezaki, Ome, JP;
Takeshi Koyama, Ome, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Disclosed is a phase-frequency comparator stabilizing a loop band width by a simple circuit, there is provided a phase-frequency comparator which is a phase-frequency comparator of inputting a reference clock and a feedback clock and outputting an up signal to a frequency synthesizer and a down signal to the frequency synthesizer, which is provided with a first phase-frequency comparing circuit, a second phase comparing circuit, and a delay circuit portion inputting the reference clock and the feedback clock and providing a predetermined relative delay to an input of the first phase-frequency comparing circuit and an input of the second phase comparing circuit, in which frequency comparison is carried out by the first phase-frequency comparing circuit, and phase comparison is carried out by the first phase-frequency comparing circuit and the second phase comparing circuit controlling a latch.