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. 04, 1979
Filed:
Apr. 14, 1978
Hiroyoshi Hashimoto, Neyagawa, JP;
Sanyo Electric Co., Ltd., Osaka, JP;
Abstract
A stabilizing circuit for a phase locked loop comprising an input terminal for receiving an input pulse signal, a voltage controlled oscillator, a phase comparator for comparing the phases of the input pulse signal and the output of the voltage controlled oscillator, and a low pass filter for filtering the output of the voltage controlled oscillator for providing a voltage control signal to the voltage controlled oscillator, characterized in that the stabilizing circuit comprises a random noise source for generating a random noise input to the input terminal which has a frequency sufficiently high with respect to the frequency of the normal input pulse signal, a switching circuit preliminarily applying the random noise input to the input terminal and responsive to the normal input pulse signal for selectively applying the normal input pulse signal to the input terminal, and an adjusting circuit for adjusting the input of the voltage controlled oscillator when the random noise input is received to a level close to the input level of the voltage controlled oscillator when the normal input pulse signal is received, whereby the operation of the phase locked loop is stabilized in a short time period after the normal input pulse signal is received.