Patents by Inventor Andrew P. Lefevre

Andrew P. Lefevre 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 instrument circuit
    Patent number: 4608462
    Abstract: An integrated circuit for a telephone instrument provides the basic (POT) service requirement. The transmit and receive channels of the circuit may be fed via controlled attenuators incorporated in a first ancillary circuit to provide hands-free operation. The circuit also includes a current-limited power supply whereby connection to a second ancillary circuit, including an audio amplifier, may be effected to provide loudspeaker operation.
    Type: Grant
    Filed: October 19, 1984
    Date of Patent: August 26, 1986
    Assignee: International Standard Electric Corporation
    Inventors: Peter F. Blomley, Kenneth A. Arton, Edward J. Whittaker, Andrew P. Lefevre