Title:
TOLL CHARGING PULSE CONTROL SYSTEM
Document Type and Number:
Japanese Patent JP3690181
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To reduce both noise in charging polarity inversion and the power consumption in calling by a charging pulse control system for a subscriber circuit.
SOLUTION: This control system is equipped with a normal electrifying circuit 2 which supplies a call current in a normal direction with a normal electrification side control signal, a reverse electrifying circuit 25 which supplies a call current in the reverse direction with a reverse electrification side control signal 29, and a mutual current generating circuit 16 which supplies a mutual current to the normal electrifying circuit 2 and reverse electrifying circuit 25 with a mutual current control signal 18 for a subscriber circuit 24 which sends a charging signal out by inverting the electrifying current polarity of a subscriber line; and the electrification is performed normally by the normal electrifying circuit 2 and only in charging polarity inversion, even the mutual current generating circuit 16 is provided with slow ON/OFF control by a 3rd filter 17 in addition to a 1st filter 5 of the normal electrifying circuit and a 2nd filter 14 of the reverse electrifying circuit 25 so as to slowly invert the polarity of the electrifying current by using the normal electrifying circuit 2, reverse electrifying circuit 25, and mutual current generating circuit 16 in combination.
Inventors:
Furukawa Yu
Application Number:
JP12943199A
Publication Date:
August 31, 2005
Filing Date:
May 11, 1999
Export Citation:
Assignee:
NEC
International Classes:
H04M15/00; H04M19/00; H04Q1/30; H04Q3/42; (IPC1-7): H04Q3/42; H04M15/00; H04M19/00; H04Q1/30
Domestic Patent References:
| JP8279863A | ||||
| JP58063262A |
Attorney, Agent or Firm:
Shiroyuki Hori