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:
Apr. 15, 1986
Filed:
Dec. 29, 1982
Applicant:
Inventor:
Tetsuro Konno, Tokyo, JP;
Assignee:
Seikosha Co., Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
H03B / ; H03L / ;
U.S. Cl.
CPC ...
331158 ; 331176 ; 3311 / ; 331179 ; 310315 ;
Abstract
An adjustable frequency crystal oscillator circuit has an adjustment capacitor which is connected in parallel, via a switching circuit, to a load capacitor of a piezoelectric vibrator. The oscillation frequency is controlled by varying the duty factor of the pulses applied to the switching circuit for switching the adjustment capacitor into and out of parallel connection with the load capacitor. The frequency-temperature characteristic is compensated for by varying the duty factor according to changes in temperature. No trimmer capacitor is needed, and the frequency-temperature characteristic is effectively compensated for over a wide temperature range.