Subscriber line card arrangement
US4984266A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 6, 1988 |
| Grant date | Jan 8, 1991 |
| Priority date | — |
| Expiry date | Sep 6, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q11/04
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A subscriber line card arrangement, in which each of eight subscriber lines is interfaced by a respective high voltage analog circuit, followed by a low voltage circuit for producing essential analog functions including over-sampled analog-to-digital and digital-to-analog conversion. A single CMOS digital signal processor (DSP) is multiplexed between each of the eight channels to perform digitial signal processing of the telephone signals in each channel. Silicon usage for the high voltage functions is reduced as is the amount of bipolar analog circuitry. Digital hardware is saved by multiplexing the DSP. The invention is useful in central offices and PABX's.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.