Patents by Inventor Frank John De Stasi

Frank John De Stasi 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: 7589517
    Abstract: A system, method, and apparatus are arranged to provide adaptive slope compensation in a switching regulator that includes an inductor. A control loop of the switching regulator is responsive to a ramp signal. A ramp generator that includes a capacitor circuit and a current source provides the ramp signal, where at least one of the current level of the current source and the value of the capacitor circuit are adjusted to vary the slope of the ramp signal. The adjustment of the ramp signal is responsive to at least one of: a set point for the output voltage of the switching regulator, a feedback voltage that is related to the output voltage, and a measured parameter associated with the inductor in the switching regulator. By dynamically adjusting the slope of the ramp signal, slope compensation is provided for a range of inductor values that can dynamically change during operation.
    Type: Grant
    Filed: July 23, 2007
    Date of Patent: September 15, 2009
    Assignee: National Semiconductor Corporation
    Inventors: Michael Eugene Broach, Frank John De Stasi
  • Patent number: 7479778
    Abstract: A system, method, and apparatus are arranged to provide adaptive slope compensation in a switching regulator that includes an inductor. A control loop of the switching regulator is responsive to a ramp signal. A ramp generator that includes a capacitor circuit and a current source provides the ramp signal, where at least one of the current level of the current source and the value of the capacitor circuit are adjusted to vary the slope of the ramp signal. The adjustment of the ramp signal is responsive to at least one of: a set point for the output voltage of the switching regulator, a feedback voltage that is related to the output voltage, and a measured parameter associated with the inductor in the switching regulator. By dynamically adjusting the slope of the ramp signal, slope compensation is provided for a range of inductor values that can dynamically change during operation.
    Type: Grant
    Filed: July 23, 2007
    Date of Patent: January 20, 2009
    Assignee: National Semiconductor Corporation
    Inventors: Michael Eugene Broach, Frank John De Stasi
  • Patent number: 7432696
    Abstract: A low-voltage current mirror circuit is provided. The low-voltage current mirror circuit includes a current mirror including first and second transistors, a buffer circuit, and a third transistor. The first transistor is the input transistor to the low-voltage current mirror circuit. Additionally, the source of the third transistor is coupled to the drain of the first transistor. The buffer circuit is configured to cause the voltage at the gate of the third transistor and the voltage at the gage of the first transistor to be substantially equal. Also, the low-voltage current mirror circuit is arranged such that the drain current provided to the third transistor is relatively small such that the Vgs of the third transistor is roughly equal to the threshold voltage VTH. Accordingly, the input voltage of the low-voltage current mirror circuit is approximately equal to Vgs-VTH.
    Type: Grant
    Filed: July 19, 2005
    Date of Patent: October 7, 2008
    Assignee: National Semiconductor Corporation
    Inventor: Frank John De Stasi
  • Patent number: 7265530
    Abstract: A system, method, and apparatus are arranged to provide adaptive slope compensation in a switching regulator that includes an inductor. A control loop of the switching regulator is responsive to a ramp signal. A ramp generator that includes a capacitor circuit and a current source provides the ramp signal, where at least one of the current level of the current source and the value of the capacitor circuit are adjusted to vary the slope of the ramp signal. The adjustment of the ramp signal is responsive to at least one of: a set point for the output voltage of the switching regulator, a feedback voltage that is related to the output voltage, and a measured parameter associated with the inductor in the switching regulator. By dynamically adjusting the slope of the ramp signal, slope compensation is provided for a range of inductor values that can dynamically change during operation.
    Type: Grant
    Filed: February 17, 2004
    Date of Patent: September 4, 2007
    Assignee: National Semiconductor Corporation
    Inventors: Michael Eugene Broach, Frank John De Stasi
  • Patent number: 6969976
    Abstract: A system, method, and apparatus are arranged to provide for current limit adjustments in a switching regulator that includes an inductor. A switched voltage divider circuit is selectively activated according to the actuation of various switching circuits in the regulator. The output of the switched voltage divider circuit is compared to a reference signal from a reference circuit to determine when a current limit is reached. At least one of the voltage divider ratio and the reference signal is adjustable in response to measurements related to the inductor saturation such that the current limit is changed to match inductor characteristics.
    Type: Grant
    Filed: June 4, 2004
    Date of Patent: November 29, 2005
    Assignee: National Semiconductor Corporation
    Inventors: Michael Eugene Broach, Frank John De Stasi
  • Patent number: 6952093
    Abstract: A system, method, and apparatus are arranged to provide small-signal compensation in a switching regulator that includes an inductor. A zero adjustment circuit is included in the system to introduce at least one zero in the closed-loop transfer function associated with the regulator. The zero adjustment circuit is responsive to a measurement signal, which is associated with one or more measured parameters associated with the inductor. By changing the location of at least one zero in response to the measurement signal it is possible to dynamically change the compensation based on variations in the inductance of the inductor. The zero adjustment circuit may be provided as a portion of the controller block of the regulator, or as a separate feedback circuit. The zero adjustment circuit can be implemented digitally as a portion of a DSP block, or as an analog function as may be desired in a particular system.
    Type: Grant
    Filed: February 17, 2004
    Date of Patent: October 4, 2005
    Assignee: National Semiconductor Corporation
    Inventors: Michael Eugene Broach, Frank John De Stasi