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. 06, 1992
Filed:
Oct. 07, 1991
Yasufumi Masaike, Kanagawa, JP;
NEC Corporation, Tokyo, JP;
Abstract
An automatic frequency control circuit includes a phase comparator, a voltage-controlled oscillator, a frequency divider, a decoder, and a discriminating circuit. The phase comparator compares a phase of an input signal of a horizontal sync signal for television with a phase of a signal phase-locked with the horizontal sync signal to generate a control voltage. The VCO outputs a VCO signal having a frequency controlled by the control voltage. The frequency divider divides a frequency of the VCO signal and outputs an intermediate frequency division ratio signal and the phase-locked signal serving as a terminal frequency division ratio output. A decoder logically processes the phase-locked signal, the intermediate frequency division ratio signal, and the VCO signal and outputs a horizontal sync signal phase-locked with the horizontal sync signal. A discriminating circuit triggered at a leading edge of a vertical sync signal for television latches the phase-locked signal and generates an even/odd field discrimination output.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile