Patents Assigned to NetPower Technologies, Inc.
  • Patent number: 7474185
    Abstract: A high-density power converter that benefits from improved packaging techniques and thermal handling capability is provided. The power converter includes a magnetic core. The converter further includes a printed circuit board providing at least one cutout for receiving a portion of the magnetic core. A circuit is magnetically coupled to the magnetic core. A stopper is configured at an edge of the cutout proximate to the circuit to hold the magnetic core at a predefined distance relative to the circuit, thereby meeting a safety distance requirement between the core and the circuit. Advanced thermal management is provided by way of a heat sink assembly to enhance the thermal-handling capability of the converter.
    Type: Grant
    Filed: July 8, 2005
    Date of Patent: January 6, 2009
    Assignee: NetPower Technologies, Inc.
    Inventors: Roger Hooey, Drue Nicholson
  • Patent number: 6940384
    Abstract: A high-density power converter that benefits from improved packaging techniques and thermal handling capability is provided. The power converter includes a magnetic core. The converter further includes a printed circuit board providing at least one cutout for receiving a portion of the magnetic core. A circuit is magnetically coupled to the magnetic core. A stopper is configured at an edge of the cutout proximate to the circuit to hold the magnetic core at a predefined distance relative to the circuit, thereby meeting a safety distance requirement between the core and the circuit. Advanced thermal management is provided by way of a heatsink assembly to enhance the thermal-handling capability of the converter.
    Type: Grant
    Filed: March 7, 2003
    Date of Patent: September 6, 2005
    Assignee: NetPower Technologies, Inc.
    Inventors: Roger Hooey, Drue Nicholson
  • Patent number: 6760235
    Abstract: Circuit and method for controlling circuitry in a power converter device during a soft-start process is provided. Synchronous rectifier control circuitry is adapted to gradually apply a gate drive signal derived from the main switch of the power converter device to a freewheeling synchronous rectifier of the switching circuitry during the soft-start process. The control circuitry gradually releases the amplitude or the pulse-width of the gate drive signal to the freewheeling synchronous rectifier to avoid a large duty ratio in the synchronous rectifier during start-up so that a negative current does not build up in the output inductor.
    Type: Grant
    Filed: September 11, 2002
    Date of Patent: July 6, 2004
    Assignee: Netpower Technologies, Inc.
    Inventors: Feng Lin, Ning Sun, Hengchun Mao, Yimin Jiang
  • Patent number: 6674658
    Abstract: A power converter device using synchronous rectifiers and method for controlling operation thereof are provided. A first synchronous rectifier is coupled to the secondary transformer winding to pass a voltage induced at the secondary winding in response to an input voltage supplied to the primary transformer winding during an on-state of a main power switch. A first drive circuit is coupled to the gate terminal of the first synchronous rectifier to selectively activate and deactivate the first rectifier in correspondence with the respective on and off states of the main power switch based on a gate voltage supplied by the first drive circuit, with at least one circuit parameter being selected in the first drive circuit for maintaining the gate voltage within a predefined range regardless of variation in the level of the input voltage.
    Type: Grant
    Filed: February 1, 2002
    Date of Patent: January 6, 2004
    Assignee: Netpower Technologies, Inc.
    Inventors: Hengchun Mao, Yimin Jiang
  • Patent number: 6574124
    Abstract: A power distribution system is provided including current sharing circuitry, current sensing and over-current protection. The system includes a plurality of power converter modules each having a current sharing signal terminal on an input side and power output terminals on an output side, the corresponding power output terminals of the several modules being connected together and adapted to power a common load; an interconnecting signal bus coupled across the current sharing signal terminals on the input side; a plurality of feedback circuits, each of which is associated with one of said modules, each feedback circuit including a comparator (error amplifier) for comparing a feedback voltage on the output side with a reference voltage to provide an error signal to the input side; the error signal conditioned to provide a current command signal to said signal bus, wherein the signal bus provides a common current command signal to drive the power converter modules.
    Type: Grant
    Filed: September 11, 2002
    Date of Patent: June 3, 2003
    Assignee: Netpower Technologies, Inc.
    Inventors: Feng Lin, Ning Sun, Hengchun Mao, Yimin Jiang
  • Patent number: 6466461
    Abstract: Circuit and method for reducing voltage level variation in a bias voltage generated in a power converter device are provided. The method allows providing a first voltage source configured to supply a first voltage during one respective mode of operation of the power converter, wherein the level of the voltage supplied by the first voltage source is directly proportional to variation in an input voltage of the converter device. The method further allows providing a second voltage source configured to supply a second voltage during another respective mode of operation of the power converter, wherein the level of the voltage supplied by the second voltage source has a generally inverse proportional relationship relative to variation in the input voltage of the converter device. At least one circuit parameter is selected in the voltage sources to adjust the respective levels of the first and second voltages.
    Type: Grant
    Filed: February 7, 2002
    Date of Patent: October 15, 2002
    Assignee: NetPower Technologies, Inc.
    Inventors: Hengchun Mao, Yimin Jiang