Subscriber line interface circuit
US6700975B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 27, 2000 |
| Grant date | Mar 2, 2004 |
| Priority date | — |
| Expiry date | Jan 11, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M19/005
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
In a subscriber line interface circuit, a device applies to a line, associated with the line interface circuit, a substantially constant line current of a first predetermined value for line voltages up to a first voltage having an absolute value which, by a predetermined amount, is lower than the supply voltage of the line interface circuit. For line voltages between the first voltage and a second voltage having an absolute value which, by a predetermined amount, is higher than the first voltage, a line current which is inversely proportional to the line voltage and of a value between said first predetermined value and a second predetermined, lower value is applied to the line. For line voltages between the second voltage and a third voltage having an absolute value which, by a predetermined amount, is higher than the second voltage, a substantially constant line current of the second predetermined value is applied to the line. For line currents of lower value than said second predetermined value, the line voltage is maintained substantially constant at the third voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.