JPS57207472A - Power supply system for telephone set - Google Patents

Power supply system for telephone set

Info

Publication number
JPS57207472A
JPS57207472A JP9235981A JP9235981A JPS57207472A JP S57207472 A JPS57207472 A JP S57207472A JP 9235981 A JP9235981 A JP 9235981A JP 9235981 A JP9235981 A JP 9235981A JP S57207472 A JPS57207472 A JP S57207472A
Authority
JP
Japan
Prior art keywords
circuit
resistor
power supply
telephone set
voltage
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.)
Pending
Application number
JP9235981A
Other languages
Japanese (ja)
Inventor
Fujio Amamiya
Naoki Matsuo
Koichi Matsumoto
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.)
Nippon Telegraph and Telephone Corp
Original Assignee
Nippon Telegraph and Telephone Corp
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 Nippon Telegraph and Telephone Corp filed Critical Nippon Telegraph and Telephone Corp
Priority to JP9235981A priority Critical patent/JPS57207472A/en
Publication of JPS57207472A publication Critical patent/JPS57207472A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M19/00—Current supply arrangements for telephone systems
    • H04M19/001—Current supply source at the exchanger providing current to substations
    • H04M19/006—Circuits for increasing the range of current supply source
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00—Reducing energy consumption in communication networks
    • Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Devices For Supply Of Signal Current (AREA)

Abstract

PURPOSE:To reduce the power for telephone input and the total power consumption per subscriber, by adjusting a DC resistor in a current supply circuit of an exchanger in response to a resistance of a subscriber line. CONSTITUTION:When a hook switch 4 is closed with off-hook and a DC loop between an exchanger and a telephone set is formed, a channel current determined with a voltage of a constant voltage power supply 1, resistance of resistors 2 and 3 and a variable resistor 6 and a DC resistance of a telephone set power supply circuit 11 flows to a subscriber line. A control circuit 10 compares a terminal voltage of the resistor 2 with a reference voltage of a reference voltage generating circuit 9 and when both the voltages are not equal, a trigger signal is outputted. Further, the variable resistor circuit 6 is operated with a trigger signal from the control circuit 10 so that a switch 7 in the variable resistor selects a plurality of resistors, and when the terminal voltage at the resistor 2 and the reference voltage are equal, the circuit 10 stops the transmission of the trigger signal and the switch stops the selection for steady state.
JP9235981A 1981-06-17 1981-06-17 Power supply system for telephone set Pending JPS57207472A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP9235981A JPS57207472A (en) 1981-06-17 1981-06-17 Power supply system for telephone set

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP9235981A JPS57207472A (en) 1981-06-17 1981-06-17 Power supply system for telephone set

Publications (1)

Publication Number Publication Date
JPS57207472A true JPS57207472A (en) 1982-12-20

Family

ID=14052205

Family Applications (1)

Application Number Title Priority Date Filing Date
JP9235981A Pending JPS57207472A (en) 1981-06-17 1981-06-17 Power supply system for telephone set

Country Status (1)

Country Link
JP (1) JPS57207472A (en)

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