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:
Dec. 28, 2010
Filed:
Dec. 17, 2008
Takashi Kawamoto, Kodaira, JP;
Takashi Kawamoto, Kodaira, JP;
Renesas Electronics Corporation, Kawasaki-shi, JP;
Abstract
The semiconductor integrated circuit incorporates a PLL circuit including a phase-frequency comparator, first and second charge pumpsand, a loop filter, a voltage-control oscillatorand a divider. The operation mode of the PLL circuit includes a standby state where locking is stopped, a lock response operation where locking is started and a steady lock operation where the locking started by the lock response operation is continued. In the steady lock operation, setting is made so that the second charge pumpis smaller in charge/discharge current than the first charge pump. The first and second charge pumpsandcharge and discharge the loop filterin response to outputs of the phase-frequency comparatorin reverse to each other in phase. In the lock response operation where locking is started, the second charge pumpis stopped from charging and discharging in reverse in phase.