JPH0353795A - Malfunction detecting system - Google Patents

Malfunction detecting system

Info

Publication number
JPH0353795A
JPH0353795A JP18930689A JP18930689A JPH0353795A JP H0353795 A JPH0353795 A JP H0353795A JP 18930689 A JP18930689 A JP 18930689A JP 18930689 A JP18930689 A JP 18930689A JP H0353795 A JPH0353795 A JP H0353795A
Authority
JP
Japan
Prior art keywords
circuit
switch
set
malfunction
feeding
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
JP18930689A
Inventor
Hideki Kikui
Original Assignee
Nec Corp
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 filed Critical Nec Corp
Priority to JP18930689A priority Critical patent/JPH0353795A/en
Publication of JPH0353795A publication Critical patent/JPH0353795A/en
Application status is Pending legal-status Critical

Links

Abstract

PURPOSE: To speedily reset the call state of a subscriber circuit by displaying the detection of malfunction in a PNPN switch at the time of feeding normally to a host controller in the malfunction detecting system of a switch circuit provided in the subscriber circuit of a telephone exchange.
CONSTITUTION: A switch circuit 4 is equipped with a PNPN switch 4a, which supplies and connects a call current to a subscriber line and switches a voltage polarity to be impressed to the subscriber line, and a PNPN switch 4b to insert and connect a resistor 6 between A and B lines at the time of feeding to a facsimile equipment and a data telephone set. When the malfunction is generated in the switch 4b, an almost '0'V is impressed to the input of a comparator 8 in a malfunction detection display circuit 7 and an output comes to a negative voltage. Then, this negative voltage becomes smaller than the value of a referring voltage 12 and the output of a comparator 9 goes to a high level and is impressed to an AND incoming path 10. At such a time, for the input of another signal to the AND circuit 10, a normal feeding signal is set to a high level, a preloop switch signal is set to a low level and a feeding stop signal is set to the low level. Then, AND is established and a malfunction detection display output is set in a latch circuit 11.
COPYRIGHT: (C)1991,JPO&Japio
JP18930689A 1989-07-21 1989-07-21 Malfunction detecting system Pending JPH0353795A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP18930689A JPH0353795A (en) 1989-07-21 1989-07-21 Malfunction detecting system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP18930689A JPH0353795A (en) 1989-07-21 1989-07-21 Malfunction detecting system

Publications (1)

Publication Number Publication Date
JPH0353795A true JPH0353795A (en) 1991-03-07

Family

ID=16239132

Family Applications (1)

Application Number Title Priority Date Filing Date
JP18930689A Pending JPH0353795A (en) 1989-07-21 1989-07-21 Malfunction detecting system

Country Status (1)

Country Link
JP (1) JPH0353795A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5475264A (en) * 1992-07-30 1995-12-12 Kabushiki Kaisha Toshiba Arrangement having multilevel wiring structure used for electronic component module
US5483101A (en) * 1993-12-10 1996-01-09 Nec Corporation Multilayer printed circuit board

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5475264A (en) * 1992-07-30 1995-12-12 Kabushiki Kaisha Toshiba Arrangement having multilevel wiring structure used for electronic component module
US5483101A (en) * 1993-12-10 1996-01-09 Nec Corporation Multilayer printed circuit board

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