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:
Aug. 31, 1999
Filed:
Sep. 29, 1997
Kuniaki Morita, Hamamatsu, JP;
Masao Noro, Hamamatsu, JP;
Yamaha Corporation, Hamamatsu, JP;
Abstract
A mixing circuit that mixes a plurality of input signals are provided. A plurality of input terminals receive the input signals, respectively. A plurality of first resistors each providing input resistance each have one end thereof connected to a corresponding one of the input terminals, and another end thereof connected to corresponding ends of the other first resistors. A first amplifier has a positive input terminal to which the another end of each of the first resistors is commonly connected. A second resistor has one end connected to the output terminal of the first amplifier, and another end connected to the negative input terminal of the first amplifier. A second amplifier has a negative input terminal to which the another end of the second resistor is connected, with a positive input terminal thereof grounded. A plurality of third resistors are connected in series between the negative input terminal of the second amplifier and the positive input terminal of the first amplifier. The third resistors have nodes located between adjacent ones thereof, and a plurality of switches are connected between the respective nodes of the third resistors and the output terminal of the second amplifier. The input signals are mixed by the mixer circuit, and an output signal of the mixer circuit is generated from the output terminal of the first amplifier.