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:
Sep. 10, 1991
Filed:
Dec. 21, 1989
Fujitsu Limited, Kawasaki, JP;
Fujitsu VLSI Limited, Kasugai, JP;
Abstract
A PLL synthesizer includes a voltage-controlled oscillator generating an output signal having a frequency based on a first signal supplied thereto, a PLL control circuit which generates a second signal based on the output signal and a set frequency, a lowpass filter having an input terminal and an output terminal, for filtering the second signal supplied through the input terminal to thereby generate the first signal supplied to the voltage-controlled oscillator through the output terminal, and a switch circuit which is coupled between the input and output terminals of the lowpass filter and which supplies the second signal directly to the voltage-controlled oscillator during a predetermined time when the set frequency is changed.