JPS5735462A - Communication current supply circuit - Google Patents

Communication current supply circuit

Info

Publication number
JPS5735462A
JPS5735462A JP11061680A JP11061680A JPS5735462A JP S5735462 A JPS5735462 A JP S5735462A JP 11061680 A JP11061680 A JP 11061680A JP 11061680 A JP11061680 A JP 11061680A JP S5735462 A JPS5735462 A JP S5735462A
Authority
JP
Japan
Prior art keywords
supply circuit
circuit
output
power supply
communication current
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
JP11061680A
Other languages
Japanese (ja)
Other versions
JPS6331149B2 (en
Inventor
Kunio Nagashima
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 JP11061680A priority Critical patent/JPS5735462A/en
Publication of JPS5735462A publication Critical patent/JPS5735462A/en
Publication of JPS6331149B2 publication Critical patent/JPS6331149B2/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 make small the size of a communication current supply circuit and to make easy circuit integration, by constituting the communication current supply circuit without using any inductive element. CONSTITUTION:Telephone sets are connected to terminals 201, 204 and an exchanging circuit 1 is to terminals 200, 203 and the communication current is given from a power supply circuit 206. The output of a differential amplifier 208 which detects the output of the power supply circuit 206 passes through a low pass filter having the cut-off frequency of 300Hz or lower and it is added with the output of a differential amplifier 210 detecting a voltage across a resistor 207 and compared with a reference voltage Es at a comparison circuit 213. The comparison circuit 213 controls the power supply circuit 206 so that the output of an addition circuit 211 can be constant. Where a transfer function from the input of the comparison circuit 213 to the output of the power supply circuit 206 is taken as A, es is an audio signal voltage, is is a current flowing to the resistor 207, and Rs is the resistance value of the resistor 207, es/is=(1+A)Rs is obtained and a greater impedance can be obtained by making greater the transfer function A.
JP11061680A 1980-08-12 1980-08-12 Communication current supply circuit Granted JPS5735462A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11061680A JPS5735462A (en) 1980-08-12 1980-08-12 Communication current supply circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11061680A JPS5735462A (en) 1980-08-12 1980-08-12 Communication current supply circuit

Publications (2)

Publication Number Publication Date
JPS5735462A true JPS5735462A (en) 1982-02-26
JPS6331149B2 JPS6331149B2 (en) 1988-06-22

Family

ID=14540323

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11061680A Granted JPS5735462A (en) 1980-08-12 1980-08-12 Communication current supply circuit

Country Status (1)

Country Link
JP (1) JPS5735462A (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06287972A (en) * 1993-04-02 1994-10-11 Nitsukon Kikai Kogyo Kk Assembly manhole

Also Published As

Publication number Publication date
JPS6331149B2 (en) 1988-06-22

Similar Documents

Publication Publication Date Title
JPS54160150A (en) Frequency selecting circuit
US4119806A (en) Subscriber's line equipment for a telephone exchange
JPS5735462A (en) Communication current supply circuit
ATE47945T1 (en) SUBSCRIPTION CIRCUIT.
JPS57121308A (en) Power amplifier
JPS5737965A (en) Two-terminal circuit
JPS54151309A (en) Supply circuit for communication current
JPS5696518A (en) Tone control circuit
JPS5673911A (en) Microwave amplifier
JPS56166613A (en) Voltage to current converting circuit
JPS5755605A (en) Differential amplifier
GB1030941A (en) Circuit arrangement for varying the level of a signal
JPS5726906A (en) Distortion rejector
JPS56169408A (en) Limiter circuit
JPS56160110A (en) Amplifying circuit
JPS5761319A (en) Electronic variable resistor
JPS5783917A (en) Inductance circuit
JPS5478954A (en) Agc amplifier circuit
JPS5696307A (en) Constant-current circuit
JPS5599874A (en) Communication current supply circuit
JPS57207412A (en) Rc active filter
JPS56772A (en) Communication current supply circuit
JPS5735461A (en) Communication current supply circuit
JPS5772415A (en) Circuir having function of band pass filter and oscillator
JPS56144644A (en) Two-wire to four-wire convertion circuit