Integrated interface circuit for driving a subscriber line
US5706343A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 16, 1996 |
| Grant date | Jan 6, 1998 |
| Priority date | — |
| Expiry date | Dec 16, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M19/005
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An integrated telephone interface circuit for driving a telephone line includes a line current sensor and a phase converter, both associated with an output stage connected to the telephone line. The circuit is equipped with a protection device against the generation of spurious signals including a comparator connected between the converter and the output stage, a control and monitoring circuit linked operatively to an output of the comparator, and a plurality of switches associated with the input side of the converter, as well as with the current sensor and the output stage. The switches are linked operatively to respective outputs of the control and monitoring circuit to reverse polarity of the line supply upon a predetermined threshold value for the comparator being exceeded.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.