Patents by Inventor William Densham

William Densham 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: 9130378
    Abstract: In a power converter, a primary winding receives an input power. In addition, multiple secondary windings transform the input power into multiple charging currents to charge a set of cells via a set of paths. The multiple secondary windings further balance the set of cells based on the charging currents. A ratio between a first turn number of a first secondary winding of the secondary windings and a second turn number of a second secondary winding of the secondary windings is determined by a nominal voltage ratio between two corresponding cells of the set of cells.
    Type: Grant
    Filed: November 27, 2013
    Date of Patent: September 8, 2015
    Assignee: O2Micro, Inc.
    Inventors: William Densham, Constantin Bucur, Flavius Lupu, Jiun Heng Goh, Stefan Maireanu
  • Patent number: 9071049
    Abstract: A circuit includes multiple battery modules and protection circuits respectively coupled to the battery modules. Each protection circuit includes a controller and a shunt circuit. The controller is coupled to one of the battery modules and detects a fault associated with the battery module. The shunt circuit is coupled to the battery module and the controller, and shunts a current around the battery module if the fault associated with the battery module is detected by the controller.
    Type: Grant
    Filed: July 12, 2013
    Date of Patent: June 30, 2015
    Assignee: O2Micro, Inc.
    Inventor: William Densham
  • Patent number: 8907625
    Abstract: A battery management chip may include a battery management unit and a vertical bus circuit. The battery management unit can monitor a cell status of multiple cells in a battery module coupled to the battery management chip in response to an instruction from a host processor. The vertical bus circuit may transfer the instruction from the host processor to the battery management unit. The vertical bus circuit may include a first receiver, a command processor and a first transmitter. The first receiver can receive a first pair of differential input data signals. The command processor can process the first pair of differential input data signals. The first transmitter can output a first pair of differential output data signals.
    Type: Grant
    Filed: July 15, 2011
    Date of Patent: December 9, 2014
    Assignee: O2Micro, Inc.
    Inventors: Allan Flippin, William Densham, Jiun Heng Goh, Constantin Bucur, Flavius Lupu, Stefan Maireanu
  • Publication number: 20140084871
    Abstract: In a power converter, a primary winding receives an input power. In addition, multiple secondary windings transform the input power into multiple charging currents to charge a set of cells via a set of paths. The multiple secondary windings further balance the set of cells based on the charging currents. A ratio between a first turn number of a first secondary winding of the secondary windings and a second turn number of a second secondary winding of the secondary windings is determined by a nominal voltage ratio between two corresponding cells of the set of cells.
    Type: Application
    Filed: November 27, 2013
    Publication date: March 27, 2014
    Applicant: O2Micro Inc.
    Inventors: William DENSHAM, Constantin BUCUR, Flavius LUPU, Jiun Heng GOH, Stefan MAIREANU
  • Patent number: 8598844
    Abstract: In a power converter, a primary winding receives an input power. In addition, multiple secondary windings transform the input power into multiple charging currents to charge a set of cells via a set of paths. The multiple secondary windings further balance the set of cells based on the charging currents. A ratio between a first turn number of a first secondary winding of the secondary windings and a second turn number of a second secondary winding of the secondary windings is determined by a nominal voltage ratio between two corresponding cells of the set of cells.
    Type: Grant
    Filed: October 21, 2011
    Date of Patent: December 3, 2013
    Assignee: O2Micro, Inc.
    Inventors: William Densham, Constantin Bucur, Flavius Lupu, Jiun Heng Goh, Stefan Maireanu
  • Publication number: 20130307550
    Abstract: A state-of-charge (SOC) indicator for a battery pack is provided. The operation of the indicator is changed from a first mode to a second mode if a mechanism is activated, and is changed to a third mode if the mechanism remains activated after a timer expires. The indicator consumes a first amount of power in the second mode, and consumes a second amount of power which is less than the first amount in the third mode. The indicator blinks with a regular frequency when the SOC is less than a threshold. A comparator compares a divided signal and a reference signal during a first time interval, and the indicator displays the SOC based upon the comparison result during a second time interval separated from the first time interval.
    Type: Application
    Filed: April 30, 2013
    Publication date: November 21, 2013
    Applicant: O2Micro Inc.
    Inventors: William DENSHAM, Laszlo LIPCSEI, Flavius LUPU
  • Publication number: 20130301173
    Abstract: A circuit includes multiple battery modules and protection circuits respectively coupled to the battery modules. Each protection circuit includes a controller and a shunt circuit. The controller is coupled to one of the battery modules and detects a fault associated with the battery module. The shunt circuit is coupled to the battery module and the controller, and shunts a current around the battery module if the fault associated with the battery module is detected by the controller.
    Type: Application
    Filed: July 12, 2013
    Publication date: November 14, 2013
    Inventor: William DENSHAM
  • Patent number: 8502503
    Abstract: A circuit includes multiple battery modules and protection circuits respectively coupled to the battery modules. Each protection circuit includes a controller and a shunt circuit. The controller is coupled to one of the battery modules and detects a fault associated with the battery module. The shunt circuit is coupled to the battery module and the controller, and shunts a current around the battery module if the fault associated with the battery module is detected by the controller.
    Type: Grant
    Filed: December 16, 2009
    Date of Patent: August 6, 2013
    Assignee: O2Micro Inc.
    Inventor: William Densham
  • Publication number: 20130019037
    Abstract: A battery management chip may include a battery management unit and a vertical bus circuit. The battery management unit can monitor a cell status of multiple cells in a battery module coupled to the battery management chip in response to an instruction from a host processor. The vertical bus circuit may transfer the instruction from the host processor to the battery management unit. The vertical bus circuit may include a first receiver, a command processor and a first transmitter. The first receiver can receive a first pair of differential input data signals. The command processor can process the first pair of differential input data signals. The first transmitter can output a first pair of differential output data signals.
    Type: Application
    Filed: July 15, 2011
    Publication date: January 17, 2013
    Inventors: Allan Flippin, William Densham, Jiun Heng Goh, Constantin Bucur, Flavius Lupu, Stefan Maireanu
  • Patent number: 8248259
    Abstract: A protection circuit includes a detection block, a timer and a protection enable block. The detection block is used to compare a monitoring signal with a reference signal and generate an alert signal if a difference between the monitoring signal and the reference signal exceeds a threshold for a first predetermined duration. The timer coupled to the detection block is used to generate an enabling signal for a second predetermined duration in response to the alert signal. The protection enable block coupled to the timer is used to generate a triggering signal for a first time duration determined by the second predetermined duration in response to the enabling signal so as to perform a protection function.
    Type: Grant
    Filed: January 16, 2009
    Date of Patent: August 21, 2012
    Assignee: O2Micro, Inc
    Inventors: Constantin Bucur, William Densham, Jiun Heng Goh, Flavius Lupu
  • Publication number: 20120081126
    Abstract: A battery monitoring system for a battery including multiple battery cells is disclosed. The battery monitoring system includes multiple first switch sets coupled across the battery cells respectively, an energy storage element, and a comparator coupled to the energy storage element via a second switch set. The energy storage element samples cell voltages of the battery cells via the first switch sets respectively. The comparator compares a respective cell voltage with a first reference signal to determine whether a fault condition occurs on a respective battery cell. The second switch set and one of the first switch sets are turned on alternately.
    Type: Application
    Filed: September 30, 2010
    Publication date: April 5, 2012
    Inventors: Stefan MAIREANU, William DENSHAM, Jiun Heng GOH, Flavius LUPU, Constantin BUCUR
  • Patent number: 8148942
    Abstract: In a power converter, a primary winding receives an input power. In addition, multiple secondary windings transform the input power into multiple charging currents to charge a set of cells via a set of paths. The multiple secondary windings further balance the set of cells based on the charging currents. A ratio between a first turn number of a first secondary winding of the secondary windings and a second turn number of a second secondary winding of the secondary windings is determined by a nominal voltage ratio between two corresponding cells of the set of cells.
    Type: Grant
    Filed: November 5, 2009
    Date of Patent: April 3, 2012
    Assignee: O2Micro International Limited
    Inventors: William Densham, Constantin Bucur, Flavius Lupu, Jiun Heng Goh, Stefan Maireanu
  • Publication number: 20120043948
    Abstract: A method includes coupling a variable output DC power source to power control circuitry, and detecting a type of the variable output DC power source in response to the coupling operation. In one embodiment, the detecting operation may include sending an interrogation signal from the power control circuitry to the variable output DC power source, and evaluating a response to the interrogation signal to determine the type of said variable output DC power source. Power control circuitry may include source type recognition circuitry configured to detect a type of a variable output DC power source in response to a coupling of the variable output DC power source to the power control circuitry.
    Type: Application
    Filed: October 31, 2011
    Publication date: February 23, 2012
    Applicant: O2MICRO INTERNATIONAL LIMITED
    Inventors: Marian Niculae, Constantin Bucur, William Densham
  • Publication number: 20120038323
    Abstract: In a power converter, a primary winding receives an input power. In addition, multiple secondary windings transform the input power into multiple charging currents to charge a set of cells via a set of paths. The multiple secondary windings further balance the set of cells based on the charging currents. A ratio between a first turn number of a first secondary winding of the secondary windings and a second turn number of a second secondary winding of the secondary windings is determined by a nominal voltage ratio between two corresponding cells of the set of cells.
    Type: Application
    Filed: October 21, 2011
    Publication date: February 16, 2012
    Inventors: William DENSHAM, Constantin BUCUR, Flavius LUPU, Jiun Heng GOH, Stefan MAIREANU
  • Patent number: 7973515
    Abstract: A power management system includes a battery pack having a battery controller and includes an adapter operable for charging the battery pack and powering a system load. The adapter generates a power recognition signal indicative of a maximum adapter power and receives a control signal. The battery controller in the battery pack receives the power recognition signal and generates the control signal to adjust an output power of the adapter according to a status of the battery pack and a status of the system load.
    Type: Grant
    Filed: June 12, 2008
    Date of Patent: July 5, 2011
    Assignee: O2Micro, Inc
    Inventors: William Densham, Han-Jung Kao, Liusheng Liu
  • Publication number: 20110101916
    Abstract: In a power converter, a primary winding receives an input power. In addition, multiple secondary windings transform the input power into multiple charging currents to charge a set of cells via a set of paths. The multiple secondary windings further balance the set of cells based on the charging currents. A ratio between a first turn number of a first secondary winding of the secondary windings and a second turn number of a second secondary winding of the secondary windings is determined by a nominal voltage ratio between two corresponding cells of the set of cells.
    Type: Application
    Filed: November 5, 2009
    Publication date: May 5, 2011
    Inventors: William DENSHAM, Constantin BUCUR, Flavius LUPU, Jiun Heng GOH, Stefan MAIREANU
  • Publication number: 20100308771
    Abstract: A battery system includes a battery pack, an electrical interface and a load discharging the battery pack. The battery pack is used to provide a power supply and includes a monitor which is configured to monitor a battery status of the battery pack. The electrical interface is coupled to the battery pack for transmitting the power supply and the battery status. The load is coupled to the battery pack through the electrical interface, and receives the power supply to discharge the battery pack and receives the battery status via a first communication bus to control the discharging of the battery pack based on the battery status.
    Type: Application
    Filed: May 20, 2010
    Publication date: December 9, 2010
    Inventor: William DENSHAM
  • Publication number: 20100308779
    Abstract: A method includes coupling a variable output DC power source to power control circuitry, and detecting a type of the variable output DC power source in response to the coupling operation. In one embodiment, the detecting operation may include sending an interrogation signal from the power control circuitry to the variable output DC power source, and evaluating a response to the interrogation signal to determine the type of said variable output DC power source. Power control circuitry may include source type recognition circuitry configured to detect a type of a variable output DC power source in response to a coupling of the variable output DC power source to the power control circuitry.
    Type: Application
    Filed: August 17, 2010
    Publication date: December 9, 2010
    Applicant: O2Micro International Limited
    Inventors: Marian Niculae, Constantin Bucur, William Densham
  • Patent number: 7800510
    Abstract: A battery pack is disclosed. The battery pack includes a battery cell and an RF cell monitor. The RF cell monitor is embedded in the battery cell and is operable for monitoring the battery cell and for generating an alert signal indicative of a predetermined condition of the battery cell.
    Type: Grant
    Filed: November 12, 2008
    Date of Patent: September 21, 2010
    Assignee: O2Micro, Inc.
    Inventor: William Densham
  • Patent number: 7777463
    Abstract: A method includes coupling a variable output DC power source to power control circuitry, and detecting a type of the variable output DC power source in response to the coupling operation. In one embodiment, the detecting operation may include sending an interrogation signal from the power control circuitry to the variable output DC power source, and evaluating a response to the interrogation signal to determine the type of said variable output DC power source. Power control circuitry may include source type recognition circuitry configured to detect a type of a variable output DC power source in response to a coupling of the variable output DC power source to the power control circuitry.
    Type: Grant
    Filed: April 25, 2005
    Date of Patent: August 17, 2010
    Assignee: O2Micro International Limited
    Inventors: Marian Niculae, Constantin Bucur, William Densham