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:
Feb. 19, 2013
Filed:
Apr. 01, 2011
Kazutoshi Sako, Kanagawa, JP;
Tomokazu Matsuzaki, Kanagawa, JP;
Kazutoshi Sako, Kanagawa, JP;
Tomokazu Matsuzaki, Kanagawa, JP;
Renesas Electronics Corporation, Kanagawa, JP;
Abstract
An oscillator circuit in accordance with an aspect of the present invention includes a filter capacitor that generates an oscillating frequency control voltage according to a charge amount accumulated based on an oscillating frequency setting current, an oscillator that changes a frequency of an oscillation signal to be output according to the oscillating frequency control voltage, a control circuit that generates a timing control signal, a frequency detection circuit that generates a frequency detection voltage based on the timing control signal, a voltage level of the frequency detection voltage being changed according to a length of the period of the oscillation signal, and a differential amplifier that continuously changes the oscillating frequency setting current according to a voltage difference between the frequency detection voltage and a reference voltage, and outputs the resultant oscillating frequency setting current to the filter capacitor.