Interface circuit for audio signal
US5300826A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 21, 1992 |
| Grant date | Apr 5, 1994 |
| Priority date | — |
| Expiry date | Jul 21, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K5/082
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An interface circuit for an audio signal includes a low-pass filter supplied with an audio signal with a DC component superposed thereon from a first circuit for extracting the DC component and a differential-input circuit. The differential-input circuit is supplied with the audio signal with the DC component superposed thereon from the first circuit and also supplied with the DC component extracted by the low-pass filter and the output of the differential-input circuit is supplied to a second circuit. In the differential-input circuit, the DC component superposed on the audio signal from the first circuit is canceled by the DC component from the low-pass filter so that only the audio signal is supplied to the second circuit. With the above described arrangement, terminal pins of an IC can be reduced in number.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.