Patents by Inventor Constantin D. Livescu

Constantin D. Livescu 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: 8037330
    Abstract: A power supply system for a server includes a first power supply, a second power supply, a first variable slope circuit, and a second variable slope circuit. The first power supply unit is adapted to activate if a load is below a predetermined level, and adapted to deactivate if the load is above the predetermined level. The second power supply unit is adapted to activate if the load is above the predetermined level, and adapted to deactivate if the load is below the predetermined level. The first and second variable slope circuits are adapted to receive information about the load applied to the power supply units. The first variable slope circuit is adapted to deactivate the first power supply unit if the load is above the predetermined level. The second variable slope circuit is to deactivate the second power supply unit if the load is below the predetermined level.
    Type: Grant
    Filed: April 7, 2008
    Date of Patent: October 11, 2011
    Assignee: Dell Products, LP
    Inventors: Constantin D. Livescu, Abey K. Mathew
  • Patent number: 7994758
    Abstract: A power supply device comprises a driver circuit, a transistor switch, and a first transistor. The driver circuit is configured to provide a stable driving signal and a floating driving signal. The transistor switch has a first terminal, a second terminal connected to a first terminal of the driver circuit, and a third terminal connected to a second terminal of the driver circuit, and is configured to prevent a reverse current based on the floating driving signal. The first transistor has a first current electrode connected to the first terminal of the transistor switch, a second current electrode connected to the first voltage reference, and a control electrode connected to the third terminal of the driver circuit, and is configured to activate and deactivate based on the stable driving signal, and further configured to regulate an input voltage to a substantially constant direct current output voltage.
    Type: Grant
    Filed: August 27, 2008
    Date of Patent: August 9, 2011
    Assignee: Dell Products, LP
    Inventors: Lucian Popescu, Constantin D. Livescu
  • Patent number: 7813149
    Abstract: A power supply includes an input filter and rectifier module, a digital control module, and a converter module. The input filter and rectifier module is configured to rectify an input voltage. The digital control module is adapted to prevent a potential saturation of a transformer by setting a maximum allowable duty cycle for a control signal transmitted to the transistor based on an input voltage. The digital control model is further adapted to reduce switching losses in the power supply by setting the control signal switching frequency, based on the input voltage. The converter module is configured to convert the input voltage into a direct current output voltage based upon the control signal.
    Type: Grant
    Filed: September 21, 2007
    Date of Patent: October 12, 2010
    Assignee: Dell Products, LP
    Inventors: Lucian Popescu, Constantin D. Livescu
  • Patent number: 7787271
    Abstract: A power supply device including a diode bridge, a converter module, and an inrush control module. The diode bridge is configured to rectify an input voltage. The converter module is coupled to the diode bridge and is configured to convert the input voltage into a direct current regulated output voltage. The inrush control module is connected to the diode bridge and is configured to gradually activate a transistor and to limit an inrush current peak value based upon a zero crossing being detected in the input voltage. A method for limiting the inrush current peak value is also disclosed.
    Type: Grant
    Filed: January 8, 2008
    Date of Patent: August 31, 2010
    Assignee: Dell Products, LP
    Inventors: Lucian Popescu, Constantin D. Livescu
  • Publication number: 20100052641
    Abstract: A power supply device comprises a driver circuit, a transistor switch, and a first transistor. The driver circuit is configured to provide a stable driving signal and a floating driving signal. The transistor switch has a first terminal, a second terminal connected to a first terminal of the driver circuit, and a third terminal connected to a second terminal of the driver circuit, and is configured to prevent a reverse current based on the floating driving signal. The first transistor has a first current electrode connected to the first terminal of the transistor switch, a second current electrode connected to the first voltage reference, and a control electrode connected to the third terminal of the driver circuit, and is configured to activate and deactivate based on the stable driving signal, and further configured to regulate an input voltage to a substantially constant direct current output voltage.
    Type: Application
    Filed: August 27, 2008
    Publication date: March 4, 2010
    Applicant: DELL PRODUCTS, LP
    Inventors: Lucian Popescu, Constantin D. Livescu
  • Publication number: 20090254768
    Abstract: A power supply system for a server includes a first power supply, a second power supply, a first variable slope circuit, and a second variable slope circuit. The first power supply unit is adapted to activate if a load is below a predetermined level, and adapted to deactivate if the load is above the predetermined level. The second power supply unit is adapted to activate if the load is above the predetermined level, and adapted to deactivate if the load is below the predetermined level. The first and second variable slope circuits are adapted to receive information about the load applied to the power supply units. The first variable slope circuit is adapted to deactivate the first power supply unit if the load is above the predetermined level. The second variable slope circuit is to deactivate the second power supply unit if the load is below the predetermined level.
    Type: Application
    Filed: April 7, 2008
    Publication date: October 8, 2009
    Applicant: DELL PRODUCTS, LP
    Inventors: Constantin D. Livescu, Abey K. Matnew
  • Publication number: 20090174386
    Abstract: A power supply device including a diode bridge, a converter module, and an inrush control module. The diode bridge is adapted to rectify an input voltage. The converter module is coupled to the diode bridge and is adapted to convert the input voltage into a direct current regulated output voltage. The inrush control module is connected to the diode bridge and is adapted to gradually activate a transistor and to limit an inrush current peak value based upon a zero crossing being detected in the input voltage. A method for limiting the inrush current peak value is also disclosed.
    Type: Application
    Filed: January 8, 2008
    Publication date: July 9, 2009
    Applicant: DELL PRODUCTS, LP
    Inventors: Lucian Popescu, Constantin D. Livescu
  • Publication number: 20090080222
    Abstract: A power supply includes an input filter and rectifier module, a digital control module, and a converter module. The input filter and rectifier module is configured to rectify an input voltage. The digital control module is adapted to prevent a potential saturation of a transformer by setting a maximum allowable duty cycle for a control signal transmitted to the transistor based on an input voltage. The digital control model is further adapted to reduce switching losses in the power supply by setting the control signal switching frequency, based on the input voltage. The converter module is configured to convert the input voltage into a direct current output voltage based upon the control signal.
    Type: Application
    Filed: September 21, 2007
    Publication date: March 26, 2009
    Applicant: DELL PRODUCTS, LP
    Inventors: Lucian Popescu, Constantin D. Livescu