CA2205320A1 - Telephone line interface circuit with voltage control - Google Patents

Telephone line interface circuit with voltage control

Info

Publication number
CA2205320A1
CA2205320A1 CA 2205320 CA2205320A CA2205320A1 CA 2205320 A1 CA2205320 A1 CA 2205320A1 CA 2205320 CA2205320 CA 2205320 CA 2205320 A CA2205320 A CA 2205320A CA 2205320 A1 CA2205320 A1 CA 2205320A1
Authority
CA
Canada
Prior art keywords
interface circuit
line interface
amplifiers
voltage control
currents
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CA 2205320
Other languages
French (fr)
Other versions
CA2205320C (en
Inventor
Reinhard Werner Rosch
Stanley Daniel Rosenbaum
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nortel Networks Ltd
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to CA002205320A priority Critical patent/CA2205320C/en
Priority claimed from CA002131295A external-priority patent/CA2131295C/en
Publication of CA2205320A1 publication Critical patent/CA2205320A1/en
Application granted granted Critical
Publication of CA2205320C publication Critical patent/CA2205320C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/22—Arrangements for supervision, monitoring or testing
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/738—Interface circuits for coupling substations to external telephone lines
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M19/00—Current supply arrangements for telephone systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M7/00—Arrangements for interconnection between switching centres

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Interface Circuits In Exchanges (AREA)

Abstract

A telephone line interface circuit comprises two unity gain d.c. amplifiers (132, 134) having outputs d.c. coupled via feed resistors to the line wires. Currents in the feed resistors are monitored via a digital control circuit (152), which can be programmed to provide desired operating conditions. The control circuit controls, via D-A converters (158, 160), currents passed by current sources (142, 148) through resistors (140, 146) at inputs of the d.c. amplifiers, thereby determining voltages at the amplifier inputs and hence on the line wires. These d.c. voltages are smoothed by capacitors (136, 138) used for coupling an a.c. signal to the d.c. amplifiers. The voltage control facilitates adaptive adjustment of the line interface circuit to the line in dependence upon the monitored currents.
CA002205320A 1993-03-17 1993-03-17 Telephone line interface circuit with voltage control Expired - Fee Related CA2205320C (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CA002205320A CA2205320C (en) 1993-03-17 1993-03-17 Telephone line interface circuit with voltage control

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CA002131295A CA2131295C (en) 1992-04-16 1993-03-17 Telephone line interface circuit with voltage control
CA002205320A CA2205320C (en) 1993-03-17 1993-03-17 Telephone line interface circuit with voltage control

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
CA002131295A Division CA2131295C (en) 1992-04-16 1993-03-17 Telephone line interface circuit with voltage control

Publications (2)

Publication Number Publication Date
CA2205320A1 true CA2205320A1 (en) 1993-10-28
CA2205320C CA2205320C (en) 2000-02-15

Family

ID=29425409

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002205320A Expired - Fee Related CA2205320C (en) 1993-03-17 1993-03-17 Telephone line interface circuit with voltage control

Country Status (1)

Country Link
CA (1) CA2205320C (en)

Also Published As

Publication number Publication date
CA2205320C (en) 2000-02-15

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Legal Events

Date Code Title Description
EEER Examination request
MKLA Lapsed