Patent · US Expired

Resistive line circuit

US4554412A · kind A · utility

6Cited by
8References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 23, 1984
Grant dateNov 19, 1985
Priority date
Expiry dateJul 23, 2004

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02D30/70
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

Resistive battery feed circuits are normally not used because of lack of power supply noise rejection and attendant crosstalk coupling. In this circuit the opamp and surrounding circuitry insure that power supply and ground noise do not couple into the tip and ring circuits as a metallic signal and improve crosstalk attenuation. In addition, the opamp is used to split the 48 volt supply.

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