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:
Dec. 16, 2025
Filed:
Jan. 16, 2023
Sanden Corporation, Gunma, JP;
SANDEN CORPORATION, Gunma, JP;
Abstract
Provided is an active filter device capable of effectively reducing common mode noise and differential mode noise and optimizing filter characteristics. The active filter device includes an inverting amplifier circuitthat inverts and amplifies a common mode voltage and a differential amplifier circuitthat differentially amplifies a differential mode voltage, and an output voltage of the inverting amplifier circuitis applied as a common mode compensation voltage to Y capacitors, an output of the differential amplifier circuitobtained by amplifying a voltage of a positive-side power supply lineis applied as a differential mode compensation voltage to a negative-side X capacitor, and an output of the differential amplifier circuitobtained by amplifying a voltage of a negative-side power supply lineis applied as a differential mode compensation voltage to a positive-side X capacitor