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.

Date of Patent:
Jul. 07, 1998

Filed:

Sep. 27, 1996
Applicant:
Inventor:

Takaaki Kawakami, Kamakura, JP;

Assignee:

Kabushiki Kaisha Toshiba, Kawasaki, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03L / ; H03L / ; G09G / ;
U.S. Cl.
CPC ...
331 / ; 331 11 ; 331 20 ; 331 34 ; 331 57 ; 331 74 ; 331179 ; 315399 ; 327156 ; 327158 ; 348540 ;
Abstract

A frequency detection circuit detects the frequency of a horizontal sync signal, and generates a mode switching signal corresponding to the detected frequency. A voltage-controlled oscillator constituting a PLL circuit has a plurality of oscillation modes obtained by dividing a frequency equal to an integer multiple of the frequency of the horizontal sync signal into a plurality of frequency ranges, and oscillates signals in the respective frequency ranges in accordance with control voltages output from a filter. The oscillation modes of the voltage-controlled oscillator are switched in accordance with the mode switching signal output from the frequency detection circuit. In the voltage-controlled oscillator, since the frequency range in each oscillation mode is narrow, the oscillation gain can be suppressed low, and a deterioration in jitter characteristics can be prevented.


Find Patent Forward Citations

Kawakami, Takaaki. (1998). Horizontal oscillation circuit capable of changing frequency (U.S. Patent No. 5777520). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/5777520

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

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