JPS54151308A - Supply circuit for communication current - Google Patents

Supply circuit for communication current

Info

Publication number
JPS54151308A
JPS54151308A JP6025978A JP6025978A JPS54151308A JP S54151308 A JPS54151308 A JP S54151308A JP 6025978 A JP6025978 A JP 6025978A JP 6025978 A JP6025978 A JP 6025978A JP S54151308 A JPS54151308 A JP S54151308A
Authority
JP
Japan
Prior art keywords
terminals
supply circuit
differential
communication
signal
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
JP6025978A
Other languages
Japanese (ja)
Other versions
JPS5846111B2 (en
Inventor
Koichi Hasegawa
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.)
NEC Corp
Original Assignee
NEC Corp
Nippon Electric Co Ltd
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 NEC Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP53060259A priority Critical patent/JPS5846111B2/en
Publication of JPS54151308A publication Critical patent/JPS54151308A/en
Publication of JPS5846111B2 publication Critical patent/JPS5846111B2/en
Expired 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

Landscapes

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

Abstract

PURPOSE:To increase the differential AC impedance of the cummunication path and to avoid attenuation of the communication signal, by providing the differential input operational amplifier which operates as a low pass active filter with the communication current supply circuit. CONSTITUTION:A pair of telephone lines are connected across the terminals 1 and 2, and ground and -48V are connected respectively to the terminals 3 and 4. If a DC load is present between the terminals 1 and 2, the circuit between the terminals 1,3 and 2,4 operates as a constant current supply circuit, which supplies current to the communication line via transistors 9 and 10. To the differential AC signal between the terminals 1 and 2, the capacitors 21 to 23 and the surrounding resistors operate as a low pass active filter together with the amplifiers 15, 16. Accordingly, the output of the amplifiers 15 and 16 are not operative in AC manner, no AC signal flows to the transistors 9 and 10, and the part between the terminals 1,3 and 2,4 is high in the impedance in AC manner.
JP53060259A 1978-05-19 1978-05-19 Call current supply circuit Expired JPS5846111B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP53060259A JPS5846111B2 (en) 1978-05-19 1978-05-19 Call current supply circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP53060259A JPS5846111B2 (en) 1978-05-19 1978-05-19 Call current supply circuit

Publications (2)

Publication Number Publication Date
JPS54151308A true JPS54151308A (en) 1979-11-28
JPS5846111B2 JPS5846111B2 (en) 1983-10-14

Family

ID=13136980

Family Applications (1)

Application Number Title Priority Date Filing Date
JP53060259A Expired JPS5846111B2 (en) 1978-05-19 1978-05-19 Call current supply circuit

Country Status (1)

Country Link
JP (1) JPS5846111B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4414433A (en) * 1980-06-20 1983-11-08 Sony Corporation Microphone output transmission circuit

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5260510A (en) * 1975-11-10 1977-05-19 Post Office Current supplying circuit of transmission bridge for telephone switching system

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5260510A (en) * 1975-11-10 1977-05-19 Post Office Current supplying circuit of transmission bridge for telephone switching system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4414433A (en) * 1980-06-20 1983-11-08 Sony Corporation Microphone output transmission circuit

Also Published As

Publication number Publication date
JPS5846111B2 (en) 1983-10-14

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