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:
Aug. 27, 1996
Filed:
Nov. 09, 1994
NEC Corporation, , JP;
Abstract
A phase comparator, a loop filter and a VCO compose a PLL. In the phase comparator, a CMI code defined by a CMI data is synchronized with a VCO clock generated in the VCO and an inverted clock of the VCO clock, respectively, to provide first and second synchronized CMI codes. The first synchronized CMI code is delayed to provide a delayed CMI code by a predetermined time dependent on a period of the VCO clock. The first and second synchronized CMI codes are subject to an exclusive OR logic calculation, thereby generating a phase difference signal. The delayed CMI code and the first synchronized CMI code are subject to an exclusive OR logic calculation, and a result of this exclusive OR logic calculation and the VCO clock are subject to an AND logic calculation to provide an enable signal. Only when the enable signal is high, the phase difference signal is sampled to be used as a phase difference signal in the PLL.