Patents by Inventor Claus N. Neesgaard

Claus N. Neesgaard 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).

  • Patent number: 7002406
    Abstract: A class-D amplifier circuit (30; 30?) providing improved open-loop error for base-band frequencies, such as the audio band, is disclosed. The amplifier circuit (30; 30?) includes a comparator (35) for generating a pulse-width-modulated output signal that is applied to an output power stage (37). An LC filter (32) is at the output of the power stage (37). The amplifier circuit (30; 30?) includes a loop filter having multiple feedback loop paths, with at least one feedback loop path coupled to the output of the power stage (37), and optionally, at least one feedback loop path coupled to the output of the LC filter (32). The transfer function (Hmae(s)) of the loop filter has a real part that has a much steeper slope (on the order of 80 dB/decade) at frequencies above the pulse-width-modulation switching frequency than the slope of its magnitude characteristic at frequencies below this switching frequency.
    Type: Grant
    Filed: May 14, 2004
    Date of Patent: February 21, 2006
    Assignee: Texas Instruments Incorporated
    Inventors: Lars Risbo, Claus N. Neesgaard