Extended feedback circuit employing capacitive coupling and sampled data filters
US6275581A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 10, 1998 |
| Grant date | Aug 14, 2001 |
| Priority date | — |
| Expiry date | Mar 10, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M1/745
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A network interface circuit employing differentially driven capacitive couplings across a high voltage isolation boundary and in which a .SIGMA./.DELTA. CODEC is positioned on the line side of the high voltage interface. In this manner, only four wires cross the high voltage boundary, namely differential pairs for transmit data and receive data. The transfer functions for setting AC and DC parameters, such as impedance matching, are provided by digital filters. Further, with the CODEC on the line side of the high voltage isolation interface, the data which crosses the interface is modulated at the .SIGMA./.DELTA. data rate and, thus, capacitive coupling can be used across the high voltage isolation boundary without the loss of DC data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.