JPS57184359A - Ring trip circuit - Google Patents

Ring trip circuit

Info

Publication number
JPS57184359A
JPS57184359A JP6903081A JP6903081A JPS57184359A JP S57184359 A JPS57184359 A JP S57184359A JP 6903081 A JP6903081 A JP 6903081A JP 6903081 A JP6903081 A JP 6903081A JP S57184359 A JPS57184359 A JP S57184359A
Authority
JP
Japan
Prior art keywords
circuit
called subscriber
current
terminals
fed
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.)
Pending
Application number
JP6903081A
Other languages
Japanese (ja)
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 JP6903081A priority Critical patent/JPS57184359A/en
Publication of JPS57184359A publication Critical patent/JPS57184359A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Devices For Supply Of Signal Current (AREA)

Abstract

PURPOSE:To realize a compact and light-weight ring trip circuit which has the low power consumption and can be converted into an IC, by connecting a telephone circuit and a low pass filter of a called subscriber via current Miller circuit. CONSTITUTION:The alternating current caused by the ringer signal is fed to a called subscriber connected between terminals 200 and 209 from a ringer signal source 213. When the called subscriber replies, the direct current is supplied from an accumulator 208 to be superposed on the alternating current. A part of these currents is supplied to a transistor TR205 through a resistance 204 to generate the voltage at a resistance 221 via a current Miller circuit. The DC component of this voltage is extracted through a low pass filter circuit 222 and fed to a comparator 224. Then a control circuit 225 switches the switch element when the DC due to a reply is detected and connects the called subscriber to an exchange circuit provided between terminals 201 and 202.
JP6903081A 1981-05-08 1981-05-08 Ring trip circuit Pending JPS57184359A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP6903081A JPS57184359A (en) 1981-05-08 1981-05-08 Ring trip circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6903081A JPS57184359A (en) 1981-05-08 1981-05-08 Ring trip circuit

Publications (1)

Publication Number Publication Date
JPS57184359A true JPS57184359A (en) 1982-11-13

Family

ID=13390769

Family Applications (1)

Application Number Title Priority Date Filing Date
JP6903081A Pending JPS57184359A (en) 1981-05-08 1981-05-08 Ring trip circuit

Country Status (1)

Country Link
JP (1) JPS57184359A (en)

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS55100776A (en) * 1979-01-26 1980-07-31 Nippon Telegr & Teleph Corp <Ntt> Answer supervisory system

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS55100776A (en) * 1979-01-26 1980-07-31 Nippon Telegr & Teleph Corp <Ntt> Answer supervisory system

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