KR970068385A - Telephone line test equipment using differential amplifier - Google Patents

Telephone line test equipment using differential amplifier Download PDF

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Publication number
KR970068385A
KR970068385A KR1019960007508A KR19960007508A KR970068385A KR 970068385 A KR970068385 A KR 970068385A KR 1019960007508 A KR1019960007508 A KR 1019960007508A KR 19960007508 A KR19960007508 A KR 19960007508A KR 970068385 A KR970068385 A KR 970068385A
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KR
South Korea
Prior art keywords
voltage
operational amplifier
resistor
internal
telephone line
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KR1019960007508A
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Korean (ko)
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KR0177361B1 (en
Inventor
이재희
Original Assignee
최종하
우진전자통신 주식회사
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Priority to KR1019960007508A priority Critical patent/KR0177361B1/en
Publication of KR970068385A publication Critical patent/KR970068385A/en
Application granted granted Critical
Publication of KR0177361B1 publication Critical patent/KR0177361B1/en

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/22—Arrangements for supervision, monitoring or testing
    • H04M3/26—Arrangements for supervision, monitoring or testing with means for applying test signals or for measuring
    • H04M3/28—Automatic routine testing ; Fault testing; Installation testing; Test methods, test equipment or test arrangements therefor
    • H04M3/30—Automatic routine testing ; Fault testing; Installation testing; Test methods, test equipment or test arrangements therefor for subscriber's lines, for the local loop

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Monitoring And Testing Of Exchanges (AREA)
  • Telephone Function (AREA)

Abstract

본 발명은 차동증폭기를 이용한 전화선로 시험장치에 관한 것으로, 특히 측정용 정전압 전원(VP)에 접속되어 있는 내부기준저항(RR)과, 상기 내부기준정항(RR)의 인입단에 접속되어 있는 제1분압회로부(20)와, 상기 제1분압회로부(20)의 출력단에 접속되어 있는 제1연산증폭기 (OP1)와, 상기 내부기준저항(RR)의 출력단에 접속되어 있는 제2 분압회로부(30)와, 상기 제2 분압회로부(30)의 출력단에 접속되어 있는 제2 연산증폭기(OP2)와, 상기 제1및 제2 연산증폭기(OP1, OP2)의 출력전압의 차에 비례한 증폭된 전압신호를 출력하는 차동증폭회로부(10)를 구비하여, 내부기준전압 양단의 전압차를 측정하고 이를통해 선로저항을 검출함에 따라 종래의 전화선로 시험장치에 비해 내부기준저항과 내부분압저항의 크기가 작아도 선로고전항을 측정할 수 있으며, 또한 선로시험시간을 단축시킬 수 있다.The present invention is connected to the inlet end of the internal reference resistance (R R) and the internal reference jeonghang (R R) which are connected to, and more particularly the constant voltage power supply (V P) for measurements on the test apparatus to the telephone line using a differential amplifier A first operational amplifier OP1 connected to the output terminal of the first voltage dividing circuit section 20 and a second operational amplifier OP2 connected to the output terminal of the internal reference resistor R R , A second operational amplifier OP2 connected to the output terminal of the second voltage dividing circuit section 30 and a second operational amplifier OP2 connected in parallel to the difference between the output voltages of the first and second operational amplifiers OP1 and OP2, And a differential amplification circuit unit 10 for outputting an amplified voltage signal. By measuring the voltage difference across the internal reference voltage and detecting the line resistance through the differential amplification circuit unit 10, the conventional reference line and the internal divided voltage It is possible to measure the line current term even if the resistance is small, As it is possible to shorten the test time.

Description

차동증폭기를 이용한 전화선로 시험장치Telephone line test equipment using differential amplifier

본 내용은 요부공개 건이므로 전문내용을 수록하지 않았음Since this is a trivial issue, I did not include the contents of the text.

제1도는 본 발명에 따른 전화선로 시험장치의 구성을 나타낸 회로도, 제2도는 종래의 전화선로 시험장치의 구성을 나타낸 회로도.FIG. 1 is a circuit diagram showing the configuration of a test apparatus with a telephone line according to the present invention; FIG. 2 is a circuit diagram showing a configuration of a conventional telephone line test apparatus; FIG.

Claims (4)

전화선로 시험장치에 있어서, 측정용 정전압 전원(VP)에 접속되어 있는 내부기준저항(RR)과, 상기 내부 기준저항(RR)의 인입단에 접속되어 있는 제1 분압회로부(20)와, 상기 제1분압회로부(20)의 출력단에 접속되어 있는 제1 연산증폭기 (OP1)와, 상기 내부기준저항(RR)의 출력단에 접속되어 있는 제2 분압회로부(30)와, 상기 제2 분압회로부(30)의 출력단에 접속되어 있는 제2 연산증폭기(OP2)와, 상기 제1및 제2연산증폭기(OP1, OP2)의 출력전압의 차에 비례한 증폭된 전압신호를 출력하는 차동증폭회로부(10)를 구비하는 것을 특징으로 하는 차동증폭기를 이용한 전화선로 시험장치.A telephone line testing apparatus comprising: an internal reference resistor (R R ) connected to a constant voltage power supply (V P ) for measurement; a first voltage dividing circuit portion (20) connected to a lead end of the internal reference resistor (R R ) A first operational amplifier OP1 connected to the output terminal of the first voltage dividing circuit section 20, a second voltage dividing circuit section 30 connected to an output terminal of the internal reference resistor R R , A second operational amplifier OP2 connected to the output terminal of the 2 voltage dividing circuit section 30 and a differential amplifier OP2 outputting an amplified voltage signal proportional to the difference between the output voltages of the first and second operational amplifiers OP1 and OP2 And an amplifier circuit section (10). 제1항에 있어서, 상기 제1 및 제2 분압회로부(20, 30)는 각각 병렬접속된 제3 내부분압저항(RD3), 제4 내부분압저항(RD4), 병렬접속된 제1 내부분압저항(RD1)과 제2 내부분압저항(RD2)으로 구성하되, 상기 제1 내부분압저항(RD1)과 제3 내부분압저항(RD3), 상기 제2 내부분압저항(RD2)과 제4 내부분압저항(RD4)은 각각 동일한 크기를 갖는 것을 특징으로 하는 차동증폭기를 이용한 전화선로 시험장치.The voltage dividing circuit according to claim 1, wherein each of the first and second voltage dividing circuit sections (20, 30) includes a third internal voltage dividing resistor (R D3 ), a fourth internal voltage dividing resistor (R D4 ) the voltage-dividing resistor (R D1) and the second internal voltage-dividing resistor (R D2), but the configuration, the first internal voltage-dividing resistor (R D1) and the third internal voltage-dividing resistor (R D3), said second internal dividing resistor (R D2 ) And the fourth internal voltage-dividing resistor (R D4 ) have the same magnitude, respectively. 제1항에 있어서, 상기 차동증폭회로부(10)는 상기 제1 및 제2 연산증폭기 (OP1, OP2)의 출력전압의 차에 비례하는 증폭된 전압신호를 출력하는 제3연산증폭기(OP3)와 상기 제1 연산증촉기(OP1)의 출력전압을 증폭하기 위해 제3 연산증폭기(OP3)의 양의 입력단에 각각 접속되어 있는 병렬접속된 제1및 제2저항(R1, R2)과, 상기 제2연산증폭기(OP2)의 출력전압을 증폭하기 위해 제3연산증폭기(OP3)의 음의 입력단에 각각 접속되어 있는 병렬접속된 가변저항(R3) 및 궤환저항(R4)으로 구성되는 것을 특징으로 하는 차동증폭기를 이용한 전화선로 시험장치.The differential amplifier circuit (10) according to claim 1, wherein the differential amplification circuit part (10) comprises a third operational amplifier (OP3) for outputting an amplified voltage signal proportional to a difference between output voltages of the first and second operational amplifiers (OP1, OP2) First and second resistors R1 and R2 connected in parallel to each other and connected to a positive input terminal of a third operational amplifier OP3 for amplifying the output voltage of the first operational amplifier OP1; And a feedback resistor R4 and a variable resistor R3 connected in parallel to the negative input terminal of the third operational amplifier OP3 for amplifying the output voltage of the second operational amplifier OP2 Telephone line test equipment using differential amplifier. 제3항에 있어서, 상기 제3 연산증폭기(OP3)의 궤환저항(R4)에 병렬접속되어 저역통과필터를 구성하여 전화선로를 통해 인입된 잡음을 제거하는 캐패시터(C)를 더 포함하는 것을 특징으로 하는 차동증폭기를 이용한 전화선로 시험장치.The apparatus according to claim 3, further comprising a capacitor (C) connected in parallel to a feedback resistor (R4) of the third operational amplifier (OP3) to constitute a low-pass filter to remove noise introduced through a telephone line Telephone line test equipment using differential amplifier. ※ 참고사항 : 최초출원 내용에 의하여 공개하는 것임.※ Note: It is disclosed by the contents of the first application.
KR1019960007508A 1996-03-20 1996-03-20 A telephone line test device using differential amplifier KR0177361B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1019960007508A KR0177361B1 (en) 1996-03-20 1996-03-20 A telephone line test device using differential amplifier

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1019960007508A KR0177361B1 (en) 1996-03-20 1996-03-20 A telephone line test device using differential amplifier

Publications (2)

Publication Number Publication Date
KR970068385A true KR970068385A (en) 1997-10-13
KR0177361B1 KR0177361B1 (en) 1999-05-15

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