JPS57188173A - Current supply circuit - Google Patents

Current supply circuit

Info

Publication number
JPS57188173A
JPS57188173A JP7322281A JP7322281A JPS57188173A JP S57188173 A JPS57188173 A JP S57188173A JP 7322281 A JP7322281 A JP 7322281A JP 7322281 A JP7322281 A JP 7322281A JP S57188173 A JPS57188173 A JP S57188173A
Authority
JP
Japan
Prior art keywords
input
operational amplifier
resistor
amplifier
supply circuit
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
JP7322281A
Other languages
Japanese (ja)
Other versions
JPS6322666B2 (en
Inventor
Masamichi Imai
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 JP7322281A priority Critical patent/JPS57188173A/en
Publication of JPS57188173A publication Critical patent/JPS57188173A/en
Publication of JPS6322666B2 publication Critical patent/JPS6322666B2/ja
Granted 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
    • H04M19/005—Feeding arrangements without the use of line transformers

Landscapes

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

Abstract

PURPOSE:To constitute a current supply circuit not using components such as a coil and a capacitor, in a channel device allocating telephone lines in which communication is made by superimposing audio signals on a DC current in a pair of communication cables. CONSTITUTION:An audio voltage is connected to an input terminal 14 and applied to an input amplifier 1 having two outputs of inversion and non-inversion. The non-inverted output of the amplifier 1 is given to a +input of an operational amplifier 2 via a resistor 8 and to a -input of an operational amplifier 3 via a resistor 12. On the othr hand, the inverted output of the amplifier 1 is inputted to a -input of the operational amplifier 2 via a resistor 9 and to a +input of the operational amplifier 3 via a resistor 13. A reference DC voltage source V+ is connected to the +input of the operational amplifier 2 and a reference DC voltage source V- is connected to the -input of the operational amplifier 3. To an overall load impedance connected between output terminals 15 and 16, the AC component by the audio signal and the DC component determined with the reference DC voltage flow.
JP7322281A 1981-05-15 1981-05-15 Current supply circuit Granted JPS57188173A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP7322281A JPS57188173A (en) 1981-05-15 1981-05-15 Current supply circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP7322281A JPS57188173A (en) 1981-05-15 1981-05-15 Current supply circuit

Publications (2)

Publication Number Publication Date
JPS57188173A true JPS57188173A (en) 1982-11-19
JPS6322666B2 JPS6322666B2 (en) 1988-05-12

Family

ID=13511921

Family Applications (1)

Application Number Title Priority Date Filing Date
JP7322281A Granted JPS57188173A (en) 1981-05-15 1981-05-15 Current supply circuit

Country Status (1)

Country Link
JP (1) JPS57188173A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0435669A2 (en) * 1989-12-27 1991-07-03 STMicroelectronics S.r.l. Output stage for telephone interface circuit and telephone interface circuit

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5537046A (en) * 1978-09-06 1980-03-14 Nec Corp Subscriber's circuit

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5537046A (en) * 1978-09-06 1980-03-14 Nec Corp Subscriber's circuit

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0435669A2 (en) * 1989-12-27 1991-07-03 STMicroelectronics S.r.l. Output stage for telephone interface circuit and telephone interface circuit

Also Published As

Publication number Publication date
JPS6322666B2 (en) 1988-05-12

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