KR970008921B1 - Prescriber line interface circuit - Google Patents

Prescriber line interface circuit Download PDF

Info

Publication number
KR970008921B1
KR970008921B1 KR94013927A KR19940013927A KR970008921B1 KR 970008921 B1 KR970008921 B1 KR 970008921B1 KR 94013927 A KR94013927 A KR 94013927A KR 19940013927 A KR19940013927 A KR 19940013927A KR 970008921 B1 KR970008921 B1 KR 970008921B1
Authority
KR
South Korea
Prior art keywords
resister
interface circuit
amplifier
voltage regulator
voltage
Prior art date
Application number
KR94013927A
Other languages
Korean (ko)
Other versions
KR960003210A (en
Inventor
Jong-Duk Jung
Original Assignee
Samsung Electronics 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 Samsung Electronics Co Ltd filed Critical Samsung Electronics Co Ltd
Priority to KR94013927A priority Critical patent/KR970008921B1/en
Publication of KR960003210A publication Critical patent/KR960003210A/en
Application granted granted Critical
Publication of KR970008921B1 publication Critical patent/KR970008921B1/en

Links

Classifications

    • 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

Landscapes

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

Abstract

In an interface circuit interfacing at least one telephone to subscriber lines, the present interface circuit comprises; the first amplifier amplifying voice signals; the voltage regulator with thermal compensating function and the first resister serially connected to the output of the first amplifier; the second resister connected between the voltage regulator and the ground; a operational amplifier where the common node of the first amplifier and the first resister is connected to the inverting input thereof; a transistor where the base is connected to the output of the operational amplifier and the emitter is to the common node of the second resister and the voltage regulator; a rectifier connected among the subscriber line, the collector of the transistor and the ground and transferring signals bidirectionally; and a voltage doubler. The circuit determines the telephone dc voltage by the dc current of the subscriber line and transfers voice signals.
KR94013927A 1994-06-20 1994-06-20 Prescriber line interface circuit KR970008921B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR94013927A KR970008921B1 (en) 1994-06-20 1994-06-20 Prescriber line interface circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR94013927A KR970008921B1 (en) 1994-06-20 1994-06-20 Prescriber line interface circuit

Publications (2)

Publication Number Publication Date
KR960003210A KR960003210A (en) 1996-01-26
KR970008921B1 true KR970008921B1 (en) 1997-05-30

Family

ID=19385654

Family Applications (1)

Application Number Title Priority Date Filing Date
KR94013927A KR970008921B1 (en) 1994-06-20 1994-06-20 Prescriber line interface circuit

Country Status (1)

Country Link
KR (1) KR970008921B1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100342241B1 (en) * 2000-06-21 2002-07-02 이인기 Telephone line interface circuit

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100342241B1 (en) * 2000-06-21 2002-07-02 이인기 Telephone line interface circuit

Also Published As

Publication number Publication date
KR960003210A (en) 1996-01-26

Similar Documents

Publication Publication Date Title
CA1202742A (en) Loop-start/ground-start line interface circuit
US5528688A (en) Telephone battery feed circuit including noise reduction circuit
IE862984L (en) Telephone power supply
KR970008921B1 (en) Prescriber line interface circuit
EP0158290B1 (en) A wide-band high voltage amplifier for telephone exchange subscriber line interface utilizing low voltage control circuitry
EP0391055A3 (en) Output stage for an operational amplifier
EP0182475B1 (en) Signal amplifier and telephone line feed circuit
JPS643387B2 (en)
US4856058A (en) Office line interface circuits
US4286123A (en) Bridge amplifier
CA2065635A1 (en) Transistor direct-coupled amplifier
JPS615669A (en) Constant current feeding circuit of subscriber circuit
JP2891782B2 (en) Output stage for telephone interface circuit
JPS60128762A (en) Telephone set circuit
JPH0787501B2 (en) Telephone power supply circuit
Pieters et al. A monolithic 70-V subscriber line interface circuit
JPS62110390A (en) Dc terminating circuit for trunk line of telephone exchange
Aull et al. A 60V IC for a transformerless trunk and subscriber line interface
JPS63206060A (en) Incoming trunk connection circuit
AU545713B2 (en) Interface arrangement
SE9702174D0 (en) A method in a subscriber line interface circuit as well as a subscriber line interface circuit
KR890016819A (en) Door phone interface circuit in key phone system
JPS61154348A (en) Feeding current limit system
GB857643A (en) Improvements in push-pull power amplifier
JPH03187505A (en) Buffer circuit

Legal Events

Date Code Title Description
A201 Request for examination
G160 Decision to publish patent application
E701 Decision to grant or registration of patent right
GRNT Written decision to grant
FPAY Annual fee payment

Payment date: 20020807

Year of fee payment: 6

LAPS Lapse due to unpaid annual fee