Title:
TELEPHONE INTERFACE CIRCUIT AND METHOD FOR TERMINATING TELEPHONE CIRCUIT DURING CALL PAUSE
Document Type and Number:
Japanese Patent JP2789086
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a telephone interface circuit that is equipped with an impedance termination during call pauses.
SOLUTION: A telephone interface circuit includes 1st and 2nd terminals 1 and 2, which are connected to a telephone line and a line termination branch 22. The line termination branch contains an intersection node 25, a 1st switch 23, a 1st impedance resistor 26, a 2nd switch 24 and a 2nd impedance resistor 27. The intersection node is connected to the ground via a 3rd switch 28. The 1st, 2nd and 3rd switches are controlled by a controller 29 through 1st, 2nd and 3rd control lines I1, I2 and I3 respectively. The circuit further includes a calling signal detector 6 and is connected to a microprocessor 30, which activates the controller at intervals when the circuit must be terminated for CLID transmission.
Inventors:
PIETORO KONSUIRIO
KARURO ANTONIINI
KARURO ANTONIINI
Application Number:
JP12135296A
Publication Date:
August 20, 1998
Filing Date:
May 16, 1996
Export Citation:
Assignee:
ETSUSE JI ETSUSE TOMUSON MIKUROERETSUTORONIKA SPA
International Classes:
H04M1/00; H04M1/57; H04M1/738; H04M19/04; (IPC1-7): H04M1/57; H04M1/00
Attorney, Agent or Firm:
Fukami Hisaro (3 outside)