Patents by Inventor Lars A. Snith

Lars A. Snith 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).

  • Apparatus in a loudspeaking telephone set for supplying power to an amplifier connected to the loudspeaker
    Patent number: 4856057
    Abstract: The invention relates to an apparatus for powering a loudspeaker amplifier (5) in a telephone set fed with a line current (ILO) from a telephone line (3). An incoming speech signal (S) is amplified (8) and sent to a loudspeaker (4) via the amplifier (5), (I6is powered via its feed connections (19, 20) from a reservoir capacitor (6). By the capacitor feed there are avoided variations in the line current (ILO) on amplification of the speech signal (S). The capacitor is recharged with the aid of the speech circuit (13), which has an amplifier means (16, 17) sensing a line voltage (UO) via a voltage sensing circuit (18). The amplifier means (16, 17) steers the line current (ILO) to a constant value responsive to the line voltage (UO) by sending a current ( to the line (3) via a resistor (R1), thus keeping constant a current I4 ) through the resistor (R1), this current being sensed by the amplifier means.
    Type: Grant
    Filed: June 21, 1988
    Date of Patent: August 8, 1989
    Assignee: Telefonaktiebolaget L M Ericsson
    Inventors: Lars A. Snith, Bengt O. Berg