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. 02, 1999
Filed:
Dec. 11, 1996
Applicant:
Inventor:
Katsumi Kusaba, Kyoto, JP;
Assignee:
Rohm Co., Ltd., Kyoto, JP;
Primary Examiner:
Int. Cl.
CPC ...
H04R / ;
U.S. Cl.
CPC ...
381 56 ; 381 58 ; 324 7631 ;
Abstract
A spectrum display device for audio use includes a first differential amplifier circuit and a first capacitor forming a low pass filter. A second differential amplifier circuit and a second capacitor form high pass filter; A band pass filter circuit is formed by the low pass filter and the high pass filter; A band selection circuit selectively sets a frequency band of the band pass filter circuit out of a plurality of predetermined frequency bands through selective setting of the operating currents of the first and second differential amplifier circuits.