Patent · US Expired

Subscriber loop current regulator

US4476351A · kind A · utility

4Cited by
2References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 25, 1982
Grant dateOct 9, 1984
Priority date
Expiry dateMar 25, 2002

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M19/001
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A current regulator for supplying dc power to a telephone line employs a resistor feed circuit in conjunction with a solid state feed circuit. The dc line current flowing through both such elements is monitored by a sensing circuit which drives the solid state element in a manner to maintain a desired magnitude of dc line current. The resistor value may be arbitrarily chosen so that the circuit power is shared in a desired proportion between the resistor and solid state element. When used in a telephone line in series with ac voice signals the regulator employs a capacitator and diode bridge arrangement to reduce the ac impedance thereof, improve longitudinal balance and allow bi-directional current.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.