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:
Nov. 09, 2004
Filed:
Nov. 12, 2002
Kazuo Kawai, Tokyo, JP;
General Research of Electronics, Inc., Tokyo, JP;
Abstract
An all pass filter capable of adjusting a center frequency and Q independently from one another, even in a high frequency band. In the filter, an input signal from an input terminal is applied to a gain control circuit and a subtraction circuit, and after a gain of an output signal of a tuning circuit is adjusted by a resistor dividing circuit, it is amplified by a first transistor in phase. An input signal not passing through the tuning circuit is amplified inversely by a second transistor. Since the transistors are connected to a common load resistor, the input signal and the output signal of the tuning circuit are subtracted and a difference voltage therebetween appears at the load resistor.