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. 15, 1994
Filed:
May. 13, 1993
Tohru Kageyama, Saitama, JP;
Pioneer Electronic Corporation, Tokyo, JP;
Abstract
This invention provides a volume apparatus, which is formed of semiconductor resistors and semiconductor switches and which reduces distortion and noise in attenuation signals. The volume apparatus, which comprises: a first semiconductor voltage dividing circuit successively attenuating an input signal and outputting attenuated signals; a first semiconductor switch circuit controlling the supply of the attenuated signals output from the first semiconductor voltage dividing circuit; a phase inversion circuit for inverting the phase of the input signal; a second semiconductor voltage dividing circuit successively attenuating the input signal output from the phase inversion circuit and outputting attenuated signals; a second semiconductor switch circuit controlling the supply of the attenuated signals output from the second semiconductor voltage dividing circuit; a volume control circuit controlling the first and second semiconductor switch circuits according to a control signal; and a differential amplifier having one of input terminals thereof connected to the output of the first semiconductor switch circuit and the other connected to the output of the second semiconductor switch circuit.