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:
Oct. 07, 2008
Filed:
Apr. 30, 2002
Edgar Sexauer, Stuttgart, DE;
Klaus Graef, Kirchheim, DE;
Edgar Sexauer, Stuttgart, DE;
Klaus Graef, Kirchheim, DE;
Dialog Semiconductor GmbH, Kirchheim/Teck-Nabern, DE;
Abstract
A circuit, which is enabling the superpositioning of different audio signals such as voice, music or ringer signals in a audio output device is achieved. The individual superpositioning can be activated and performed by a combination of resistors and switches without the need of an additional mixing amplifier as in prior art. One common output stage is used for all the signals activated and superpositioned. The adjustment of the amplitude of the output signal, which can be used for the volume adjustment of a loudspeaker, is provided by a precise amplitude setting via the gain control stages of an inverting voltage amplifier through a current-voltage conversion. Said current-voltage conversion is performed by a string of resistors activated by a string of correspondent switches. This circuit reduces the power consumption, the chip area required and the offset and improves the power supply rejection rate (PSSR).