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:
Nov. 06, 2001
Filed:
Oct. 07, 1998
Muneo Fukaishi, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
In a phase comparator, a first data fetching circuit fetches an input signal in response to a transition timing of a clock signal having a frequency about half that of the input signal, and a second data fetching circuit fetches the output signal of the first data fetching circuit in response to a transition timing of an inverted signal of the clock signal. A first exclusive OR performs an exclusive OR operation upon the input signal and the output signal of the first data fetching circuit. and a second exclusive OR circuit performs an exclusive OR operation upon the output signals of the first and second data fetching circuits. An inverter inverts the output signal of the first exclusive OR circuit. A first AND circuit performs an AND operation upon the output signal of the second data fetching circuit and the output of the exclusive OR circuit, a second AND circuit performs an AND operation upon the output signal of the first exclusive OR circuit and the output of the first AND circuit to generate a leading signal, and a third AND circuit performs an AND operation upon the output signal of the inverter and the output of the,first AND circuit to generate a lagging signal.