Patents by Inventor Christopher James Speyer

Christopher James Speyer 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).

  • Protection circuit for a subscriber line interface circuit
    Patent number: 7907381
    Abstract: The present invention provides a protection circuit coupled to a tip lead and a ring lead in a subscriber line interface circuit formed on a silicon substrate. The protection circuit includes first and second diodes formed on the silicon substrate and coupled to the tip lead and the ring lead, respectively. The first and second diodes are configured to provide a path from the tip lead or the ring lead to ground in response to a positive voltage at the tip lead or the ring lead. The protection circuit also includes a silicon-controlled rectifier formed on the silicon substrate and configured to provide, in response to a negative voltage at the tip lead or the ring lead, a path from the tip lead or the ring lead to ground via the silicon-controlled rectifier.
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: March 15, 2011
    Assignee: Zarlink Semiconductor (US) Inc.
    Inventor: Christopher James Speyer
  • PROTECTION CIRCUIT FOR A SUBSCRIBER LINE INTERFACE CIRCUIT
    Publication number: 20090231768
    Abstract: The present invention provides a protection circuit coupled to a tip lead and a ring lead in a subscriber line interface circuit formed on a silicon substrate. The protection circuit includes first and second diodes formed on the silicon substrate and coupled to the tip lead and the ring lead, respectively. The first and second diodes are configured to provide a path from the tip lead or the ring lead to ground in response to a positive voltage at the tip lead or the ring lead. The protection circuit also includes a silicon-controlled rectifier formed on the silicon substrate and configured to provide, in response to a negative voltage at the tip lead or the ring lead, a path from the tip lead or the ring lead to ground via the silicon-controlled rectifier.
    Type: Application
    Filed: March 12, 2008
    Publication date: September 17, 2009
    Inventor: Christopher James Speyer