Patents by Inventor Sean Xiao

Sean Xiao 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).

  • Publication number: 20080315855
    Abstract: A voltage generator is used for generating a voltage reference with high power supply rejection. One embodiment of the circuit includes a voltage regulator and a bandgap voltage circuit and an amplifier. The voltage regulator including an input node is coupled to an external power supply for generating a regulated voltage source. A bandgap voltage circuit includes a first and a second resistor and a first and a second transistor to generate a voltage difference between the base-to-emitter voltages of the first and the second transistors. The second resistor is coupled to the first resistor and the first transistor for generating the first predetermined voltage in response to the voltage difference. An amplifier circuit is coupled to the first transistor of the bandgap voltage circuit for receiving a first amplifying signal and generating an amplified signal so as to regulate the regulated voltage source.
    Type: Application
    Filed: June 19, 2007
    Publication date: December 25, 2008
    Inventors: Sean Xiao, Tom Tang, Guoxing Li
  • Patent number: 7466104
    Abstract: A system and method for cell balancing with smart low-voltage control circuit. The cell balancing system comprises a plurality of battery cells, an external bypass path for each cell, an internal bypass path for each cell, an input terminal receiving an enable signal for each cell, an input terminal receiving a selection signal, and a cell balancing unit for generating a configuration signal to conduct the external bypass path or internal bypass path. The enable signal is configured to enable a bypass current of each cell, and the selection signal is configured to select the external bypass path or internal bypass path. The cell balancing unit is employed to receive signals from input terminals, and generate a configuration signal to control the conductance of external bypass paths or internal bypass paths.
    Type: Grant
    Filed: October 13, 2006
    Date of Patent: December 16, 2008
    Assignee: O2 Micro International Limited
    Inventors: Wei Wang, Guoxing Li, Sean Xiao
  • Publication number: 20080150487
    Abstract: A battery pre-charging circuit. The pre-charging circuit comprises a pre-charging path, a pre-charging switch and a low-voltage pre-charging circuit. The pre-charging path is coupled between a charger and a battery for providing a pre-charging current from the charger to the battery. The pre-charging switch is coupled to the pre-charging path for conducting along the pre-charging path. The low-voltage pre-charging circuit coupled to the pre-charging switch for controlling the pre-charging switch. The low-voltage pre-charging circuit is configured to switch on the pre-charging switch when a battery voltage over the battery is below a first battery voltage level.
    Type: Application
    Filed: December 21, 2006
    Publication date: June 26, 2008
    Inventors: Shiqiang Liu, Guoxing Li, Sean Xiao, Liusheng Liu
  • Patent number: 7388200
    Abstract: A sensing method includes exposing a nano-transducer having a controlled surface to a sample including at least one species. Adsorption of the species on the nano-transducer is transduced to a measurable signal as a function of time. Desorption of the species from the nano-transducer is also transduced to a measurable signal as a function of time. A residence time of the at least one species adsorbed on the nano-transducer is extracted from the measurable signals. The adsorption and desorption each define an individual measurable event.
    Type: Grant
    Filed: October 19, 2006
    Date of Patent: June 17, 2008
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Duncan R. Stewart, William M. Tong, R. Stanley Williams, Philip J. Kuekes, Sean Xiao-an Zhang, Kevin F. Peters, Kenneth J. Ward
  • Publication number: 20080116490
    Abstract: A sensing method includes exposing a nano-transducer having a controlled surface to a sample including at least one species. Adsorption of the species on the nano-transducer is transduced to a measurable signal as a function of time. Desorption of the species from the nano-transducer is also transduced to a measurable signal as a function of time. A residence time of the at least one species adsorbed on the nano-transducer is extracted from the measurable signals. The adsorption and desorption each define an individual measurable event.
    Type: Application
    Filed: October 19, 2006
    Publication date: May 22, 2008
    Inventors: Duncan R. Stewart, William M. Tong, R. Stanley Williams, Philip J. Kuekes, Sean Xiao-an Zhang, Kevin F. Peters, Kenneth J. Ward
  • Publication number: 20080100564
    Abstract: An electronically addressable display comprises a substrate, at least one polarization-type, electrical field switchable molecular colorant associated with the substrate, and an addressing device mounted for selectively switching the at least one molecular colorant between at least two visually distinguishable states. Electronic devices including the electronically addressable displays and methods of manufacturing the electronically addressable display are also disclosed.
    Type: Application
    Filed: October 26, 2006
    Publication date: May 1, 2008
    Inventors: Kent D. Vincent, Sean Xiao-An Zhang, Zhang-Lin Zhou
  • Publication number: 20080088277
    Abstract: A system and method for cell balancing with smart low-voltage control circuit. The cell balancing system comprises a plurality of battery cells, an external bypass path for each cell, an internal bypass path for each cell, an input terminal receiving an enable signal for each cell, an input terminal receiving a selection signal, and a cell balancing unit for generating a configuration signal to conduct the external bypass path or internal bypass path. The enable signal is configured to enable a bypass current of each cell, and the selection signal is configured to select the external bypass path or internal bypass path. The cell balancing unit is employed to receive signals from input terminals, and generate a configuration signal to control the conductance of external bypass paths or internal bypass paths.
    Type: Application
    Filed: October 13, 2006
    Publication date: April 17, 2008
    Inventors: Wei Wang, Guoxing Li, Sean Xiao
  • Patent number: 7345302
    Abstract: The invention described herein includes a molecular switch, comprising: a donor subunit; an acceptor subunit; and an aromatic bridging subunit comprising one or more bridging groups for bonding the donor subunit to the aromatic bridging subunit and for bonding the acceptor subunit to the aromatic bridging subunit wherein the aromatic bridging subunit is conformable in a manner effective for polarizing and de-polarizing the molecular switch at a low electric field voltage.
    Type: Grant
    Filed: September 21, 2004
    Date of Patent: March 18, 2008
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Sean Xiao-An Zhang, Kent Vincent, Zhang-Lin Zhou, R. Stanley Williams
  • Publication number: 20080022927
    Abstract: A microfluidic device for controllably moving a material of interest includes a holding cavity configured to hold the material of interest and at least one actuator configured to induce an activation material to expand or contract. Expansion of the activation material decreases the size of the holding cavity to cause the material of interest to be released from the holding cavity and contraction of the activation material increases the size of the holding cavity to cause the material of interest to be received into the holding cavity. The at least one actuator is operable at multiple levels between a zero induction level to a maximum induction level on the activation material to thereby controllably expand or contract the holding cavity to release or receive a specified volume of the material of interest.
    Type: Application
    Filed: July 28, 2006
    Publication date: January 31, 2008
    Inventors: Sean Xiao-An Zhang, Patricia A. Beck, Janice H. Nickel
  • Patent number: 7294526
    Abstract: An optical sensor is provided, comprising (a) a silicon nanowire of finite length having an electrical contact pad at each end thereof; and (b) a plurality of self-assembled molecules on a surface of the silicon nanowire, the molecules serving to modulate electrical conductivity of the silicon nanowire by either a reversible change in dipole moment of the molecules or by a reversible molecule-assisted electron/energy transfer from the molecules onto the silicon nanowire. Further, a method of making the optical sensor is provided. The concept of molecular self-assembly is applied in attaching functional molecules onto silicon nanowire surfaces, and the requirement of molecule modification (hydroxy group in molecules) is minimal from the point view of synthetic difficulty and compatibility. Self-assembly will produce well-ordered ultra-thin films with strong chemical bonding on a surface that cannot be easily achieved by other conventional methods.
    Type: Grant
    Filed: August 12, 2004
    Date of Patent: November 13, 2007
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Zhiyong Li, Yong Chen, Sean Xiao-An Zhang
  • Publication number: 20070257642
    Abstract: A monitoring circuit for monitoring a plurality of battery cells of a battery pack includes a plurality of temperature sensors, an analog to digital converter (ADC) and a processor. The plurality of temperature sensors is used for sensing temperatures of the plurality of battery cells and outputting a plurality of analog temperature voltage signals representative of the temperature of the plurality of battery cells. The analog to digital converter (ADC) is adapted to receive the plurality of analog temperature voltage signals and to convert each of the plurality of analog temperature voltage signals to a plurality of individual digital signals. The processor is adapted to generate an alert signal when an individual digital signal is not within a predetermined range.
    Type: Application
    Filed: April 24, 2007
    Publication date: November 8, 2007
    Inventors: Sean Xiao, Kevin Sheng, Guoxing Li, Liusheng Liu
  • Publication number: 20070188950
    Abstract: A protection device for non-common ground buses is disclosed. The protection circuit includes a controller, a level shifter, a first group of switches, and a second group of switches. The controller together with the level shifter controls the first group and second group of switches. The non-common ground buses will be isolated when at least one group of the switches are turned off in an abnormal condition.
    Type: Application
    Filed: December 27, 2006
    Publication date: August 16, 2007
    Inventors: Liusheng Liu, Guoxing Li, Shiqiang Liu, Sean Xiao
  • Publication number: 20070075684
    Abstract: A circuit is used for controlling charging and discharging a battery. The circuit comprises a first MOSFET for controlling discharging the battery, and a second MOSFET coupled in series to the battery and the first MOSFET for controlling charging the battery. The first and second MOSFETs have body diodes respectively, and the first body diode of the first MOSFET and the second body diode of the second MOSFET are coupled in opposite directions. A load is coupled to the battery and a common node between the first and second MOSFETs such that power in the battery is delivered to said load when the first MOSFET is turned on. The circuit further comprises a power source coupled to the second switch in series and power is delivered from the power source to the battery when the first and second MOSFETs are turned on.
    Type: Application
    Filed: August 22, 2006
    Publication date: April 5, 2007
    Inventors: Shiqiang Liu, Sean Xiao, Guoxing Li, Liusheng Liu
  • Publication number: 20060176019
    Abstract: A communication circuit is used for transmitting data between a plurality of devices which have non-common ground voltages. The communication circuit comprises a plurality of transmitting input nodes coupled to the devices, respectively, a transmitting current path, a plurality of receiving output nodes coupled to the devices, respectively, and a receiving current path. The transmitting current path is coupled to the transmitting input nodes. The current through the transmitting current path is varied according to the input signal of the transmitting input nodes. The receiving current path is coupled to the receiving output nodes. The current through the receiving current path is varied according to the current of the transmitting current path such that data is transmitted from the transmitting input nodes to the receiving output nodes.
    Type: Application
    Filed: November 18, 2005
    Publication date: August 10, 2006
    Inventors: Sean Xiao, Oleksandr Kokorin
  • Patent number: 6995312
    Abstract: A bistable molecular switch can have a highly conjugated first state and a less conjugated second state. The bistable molecular switch can be configured such that application of an electric field reversibly switches the molecular switch from the first state to the second state. Additionally, the bistable molecular switch can include a hydrophobic moiety and a hydrophilic moiety. Such molecular switches can be incorporated into a thin film as part of a molecular switch system which can include a layer of molecular switches between a first electrode layer and a second electrode layer. The layer of molecular switches can have substantially all of the molecular switches having their hydrophilic moiety oriented in the same direction. An electric potential can then be induced between the first and second electrode layers sufficient to switch the molecular switches from the first or second state to the second or first state, respectively.
    Type: Grant
    Filed: February 24, 2004
    Date of Patent: February 7, 2006
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Zhang-Lin Zhou, Sean Xiao-An Zhang
  • Patent number: 6951672
    Abstract: Ceramic pigment-based, chemically-modified porous coatings can be used for enhancing image permanence of ink-jet image printing. Specifically, a porous coated media sheet, comprising a media substrate, having a porous coating coated thereon comprising a modified ceramic pigment including a fixer group and a stabilizer group, each covalently attached to the ceramic pigment is disclosed. Additionally, a method and system for preparing permanent ink-jet images is also provided.
    Type: Grant
    Filed: July 30, 2003
    Date of Patent: October 4, 2005
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Kent D. Vincent, Sivapackia Ganapathiappan, Sean Xiao-An Zhang, Palitha Wickramanayake
  • Patent number: 6867427
    Abstract: Molecular systems are provided for electric field activated switches, such as optical switches. The molecular system has an electric field induced band gap change that occurs via one of the following mechanisms: (1) molecular conformation change; (2) change of extended conjugation via chemical bonding change to change the band gap; or (3) molecular folding or stretching. Nanometer-scale reversible optical switches are thus provided that can be assembled easily to make a variety of optical devices, including optical displays.
    Type: Grant
    Filed: July 10, 2003
    Date of Patent: March 15, 2005
    Assignee: Hewlett-Packard Development Company, LP.
    Inventors: Sean Xiao-An Zhang, R. Stanley Williams, Kent D. Vincent
  • Patent number: 6815706
    Abstract: An optical sensor is provided, comprising (a) a silicon nanowire of finite length having an electrical contact pad at each end thereof; and (b) a plurality of self-assembled molecules on a surface of the silicon nanowire, the molecules serving to modulate electrical conductivity of the silicon nanowire by either a reversible change in dipole moment of the molecules or by a reversible molecule-assisted electron/energy transfer from the molecules onto the silicon nanowire. Further, a method of making the optical sensor is provided. The concept of molecular self-assembly is applied in attaching functional molecules onto silicon nanowire surfaces, and the requirement of molecule modification (hydroxy group in molecules) is minimal from the point view of synthetic difficulty and compatibility. Self-assembly will produce well-ordered ultra-thin films with strong chemical bonding on a surface that cannot be easily achieved by other conventional methods.
    Type: Grant
    Filed: December 17, 2002
    Date of Patent: November 9, 2004
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Zhiyong Li, Yong Chen, Sean Xiao-An Zhang
  • Publication number: 20040165806
    Abstract: A bistable molecular switch can have a highly conjugated first state and a less conjugated second state. The bistable molecular switch can be configured such that application of an electric field reversibly switches the molecular switch from the first state to the second state. Additionally, the bistable molecular switch can include a hydrophobic moiety and a hydrophilic moiety. Such molecular switches can be incorporated into a thin film as part of a molecular switch system which can include a layer of molecular switches between a first electrode layer and a second electrode layer. The layer of molecular switches can have substantially all of the molecular switches having their hydrophilic moiety oriented in the same direction. An electric potential can then be induced between the first and second electrode layers sufficient to switch the molecular switches from the first or second state to the second or first state, respectively.
    Type: Application
    Filed: February 24, 2004
    Publication date: August 26, 2004
    Inventors: Zhang-Lin Zhou, Sean Xiao-An Zhang
  • Publication number: 20040113165
    Abstract: An optical sensor is provided, comprising (a) a silicon nanowire of finite length having an electrical contact pad at each end thereof; and (b) a plurality of self-assembled molecules on a surface of the silicon nanowire, the molecules serving to modulate electrical conductivity of the silicon nanowire by either a reversible change in dipole moment of the molecules or by a reversible molecule-assisted electron/energy transfer from the molecules onto the silicon nanowire. Further, a method of making the optical sensor is provided. The concept of molecular self-assembly is applied in attaching functional molecules onto silicon nanowire surfaces, and the requirement of molecule modification (hydroxy group in molecules) is minimal from the point view of synthetic difficulty and compatibility. Self-assembly will produce well-ordered ultra-thin films with strong chemical bonding on a surface that cannot be easily achieved by other conventional methods.
    Type: Application
    Filed: December 17, 2002
    Publication date: June 17, 2004
    Inventors: Zhiyong Li, Yong Chen, Sean Xiao-An Zhang