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:
Oct. 15, 2002
Filed:
Aug. 03, 2001
Naohiro Matsui, Tokyo, JP;
NEC Corporation, , JP;
Abstract
BPF having a band width of |reference signal f -mixer output signal f | is connected to a phase comparator. When an output signal corresponding to the passage of this band width has been obtained, a changeover switch is turned OFF. Upon detection such that the PLL circuit is unlockable, an output signal is obtained from an offset differential pair circuit, the changeover switch is turned ON, and the time constant of LPF is reduced to shorten the lock-up time, and the voltage applied to VCO is made larger than the usual voltage. By virtue of this construction, a PLL circuit of an analog system can be realized which can shorten the lock-up time and, in addition, can reduce noise and spurious harmonics.