Patents by Inventor Bruno Defretin

Bruno Defretin has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Telephone line current modulator
    Patent number: 5420919
    Abstract: A telephone set connected to a telephone line including a supply circuit providing an output current which is an increasing function of the voltage available on the telephone line; a speech amplifier supplied by the output current; and a modulator having a quiescent current and operable to inject into the line a modulation current proportional to a speech signal. The modulator incorporates the supply circuit, the current consumed by the modulator being essentially the current provided to the amplifier by the supply circuit.
    Type: Grant
    Filed: January 28, 1993
    Date of Patent: May 30, 1995
    Assignee: SGS-Thomson Microelectronics S.A.
    Inventors: Thierry Arnaud, Bruno Defretin
  • Signal compression circuit, particularly for a telephone set
    Patent number: 4894862
    Abstract: The Invention relates to a signal compression circuit, more particularly for a telephone set of the handsfree-type, comprising a preamplifier (10), the input of which is connected with an input signal to be processed, and a preamplifier gain control device (11) for servo-controlling, to a predetermined value, the output signal amplitude of the preamplifier, in which the gain control device (11) is associated with a circuit (C, 15, 16) determining two time constants, which respectively control the increase or decrease speed of the preamplifier gain (10) in relation with the input signal amplitude (Vin).
    Type: Grant
    Filed: July 19, 1988
    Date of Patent: January 16, 1990
    Assignee: SGS-Thomson Microelectronics S.A.
    Inventors: Bruno Defretin, Thierry Arnaud
  • Subscriber telephone set with amplified loudspeaker reception with reduction of gain in the case of an insufficient power supply
    Patent number: 4750203
    Abstract: The invention relates to a subscriber telephone set with amplified reception loudspeaker.To avoid distortion of the signals transmitted to this loudspeaker should the power supply of the line be insufficient, it is provided for the amplifier feeding this loudspeaker to have its gain controlled by a signal resulting from the measurement of current passing through a shunt regulator serving for supplying the amplifier.
    Type: Grant
    Filed: December 24, 1985
    Date of Patent: June 7, 1988
    Assignee: Thomson-CSF
    Inventor: Bruno Defretin
  • Subscriber telephone line interface circuit with reduced power stand-by mode
    Patent number: 4709388
    Abstract: A subscriber telephone line interface circuit is provided with reduced power stand-by mode. For 90% of the time such circuits only have a function of monitoring the line. Means are described for considerably reducing the power consumption of the circuit during such monitoring periods. The reduction is provided essentially by modifying the construction of the output stages connected to the telephone line; these stages become generators of a fixed voltage for biasing the line when the circuit is in monitoring mode.
    Type: Grant
    Filed: February 12, 1986
    Date of Patent: November 24, 1987
    Assignee: Thomson-CSF
    Inventor: Bruno Defretin