Patents Assigned to O2Micro International
  • Patent number: 8836290
    Abstract: A monitoring circuit for accurately monitoring a voltage level from each of a plurality of battery cells of a battery pack includes an analog to digital converter (ADC) and a processor. The ADC is configured to accept an analog voltage signal from each of the plurality of battery cells and convert each analog voltage signal to a digital signal representative of an accurate voltage level of each battery cell. The processor receives such signals and provides a safety alert signal based on at least one of the signals. The ADC resolution may be adjustable. A balancing circuit provides a balancing signal if at least two of the digital signals indicate a voltage difference between two cells is greater than a battery cell balance threshold. An electronic device including such monitoring and balancing circuits is also provided. Various methods are also provided.
    Type: Grant
    Filed: August 22, 2011
    Date of Patent: September 16, 2014
    Assignee: O2MIcro International Limited
    Inventors: Liusheng Liu, Guoxing Li
  • Patent number: 8830159
    Abstract: A method according to one embodiment may include supplying power to an LED array having at least a first string of LEDs and a second string of LEDs coupled in parallel, each of the strings includes at least two LEDs. The method of this embodiment may also include comparing a first feedback signal from the first string of LEDs and a second feedback signal from the second string of LEDs. The first feedback signal is proportional to current in said first string of LEDs and said second feedback signal is proportional to current in said second string of LEDs. The method of this embodiment may also include controlling a voltage drop of at least the first string of LEDs to adjust the current of the first string of LEDs relative to the second string of LEDs, based on, at least in part, the comparing of the first and second feedback signals. Of course, many alternatives, variations, and modifications are possible without departing from this embodiment.
    Type: Grant
    Filed: December 7, 2010
    Date of Patent: September 9, 2014
    Assignee: O2Micro International Limited
    Inventors: Da Liu, Yung-Lin Lin
  • Patent number: 8738827
    Abstract: An interface circuit provides communication between a memory card and a host device. The interface circuit includes first and second sets of pins and a control unit. The control unit enables the first set of pins and disables the second set of pins when transferring a first set of signals in a first mode via the first set of pins, and disables the first set of pins and enables the second set of pins when transferring a second set of signals in a second mode via the second set of pins. The control unit transfers a clock signal of the second set of signals by differential signaling in the second mode via a clock pin of the second set of pins. A signal transfer in the second mode is at a greater speed than a signal transfer in the first mode.
    Type: Grant
    Filed: May 25, 2012
    Date of Patent: May 27, 2014
    Assignee: O2Micro International Ltd.
    Inventor: Miki Takahashi
  • Patent number: 8629649
    Abstract: A flexible dual mode battery charger that charges a battery in two different modes, depending on the difference between the adapter voltage and the battery voltage, with a smooth transition between these two modes and the charging current remains relatively constant during the transition is provided in this application. At a lower battery level, the dual mode battery charger charges the battery as a LDO charger and when battery voltage is very close to the adapter voltage, the charger migrates its operating mode from the LDO mode to the boost mode and charges the battery as a boost charger. This flexible battery charger uses one common control circuit for controlling the operations of the LDO charger and the boost charger. The switching operation from one operation mode to other operation mode is smooth.
    Type: Grant
    Filed: July 14, 2011
    Date of Patent: January 14, 2014
    Assignee: O2Micro International, Ltd.
    Inventors: Guoyong Guo, Dan Nie
  • Patent number: 8587264
    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: October 31, 2011
    Date of Patent: November 19, 2013
    Assignee: O2Micro International Limited
    Inventors: Marian Niculae, Constantin Bucur, William L. Densham
  • Patent number: 8581552
    Abstract: A battery pack including at least one battery cell, a switch, and battery state monitoring circuitry. The battery state monitoring circuitry may be configured to control an ON resistance of the switch to a first ON resistance when the switch is ON and the battery pack is in a stand-by-state and to control the ON resistance to a second ON resistance when the switch is ON and said battery pack is not in said stand-by-state, the first ON resistance greater than the second ON resistance. A cordless electrical device and method consistent with embodiments are also provided.
    Type: Grant
    Filed: March 23, 2010
    Date of Patent: November 12, 2013
    Assignee: O2Micro International Limited
    Inventors: Constantin Bucur, Marian Niculae
  • Patent number: 8376611
    Abstract: A temperature detection circuit includes a sensor, an integrated circuit (IC) chip, and a resistor. The sensor is operable for sensing a temperature. The IC chip can compare a sense voltage indicative of the temperature with a threshold voltage indicative of a temperature threshold to determine a temperature condition. The IC chip has a substantially constant parameter. The resistor is externally coupled to the IC chip. The IC chip maintains a current ratio, including a ratio of a first current flowing through the sensor to a second current flowing through the resistor, equal to the substantially constant parameter.
    Type: Grant
    Filed: March 31, 2010
    Date of Patent: February 19, 2013
    Assignee: O2Micro International Limited
    Inventors: Guoxing Li, Xiaohu Tang
  • Patent number: 8350534
    Abstract: A method for efficiently charging a battery. The method includes producing a first signal having a voltage level dependent on the voltage of the battery, comparing the voltage level of the first signal with a settable voltage representative of a maximum battery charging current, and producing a second signal representative of a charging current to be provided to the battery, the second signal having a voltage level selected to be the lower voltage level between the first signal and the settable voltage.
    Type: Grant
    Filed: July 19, 2009
    Date of Patent: January 8, 2013
    Assignee: O2Micro International, Ltd.
    Inventors: Marian Niculae, Constantin Bucur
  • Patent number: 8346977
    Abstract: According to one aspect there is disclosed an apparatus. The apparatus may include a first device.
    Type: Grant
    Filed: August 10, 2010
    Date of Patent: January 1, 2013
    Assignee: O2Micro International Limited
    Inventors: Xiaojun Zeng, Kaiya Sheng
  • Patent number: 8344694
    Abstract: A battery circuit including a first battery cell with a first parameter having a first value and a second battery cell with a second parameter having a second value. The second battery cell is coupled to the first battery cell in series. The battery circuit further includes a magnetic device operable for storing energy transferred from the first battery cell via a first winding coupled to the first battery cell and for releasing the stored energy to the second battery cell via a second winding coupled to the second battery cell if the first value of the first parameter is greater than the second value of the second parameter.
    Type: Grant
    Filed: April 12, 2012
    Date of Patent: January 1, 2013
    Assignee: O2Micro International, Ltd.
    Inventors: Chutao Zhang, Songtao Chen
  • Patent number: 8310206
    Abstract: An apparatus includes battery gauge circuitry implemented on an integrated circuit. The battery gauge circuitry includes a plurality of switches that individually open in response to a voltage reduction on a battery cell associated with a respective one of the switches. The battery gauge circuitry also includes a logic device that determines if at least one of the switches is open. The battery gauge circuitry also includes a register that stores data that indicates if at least one switch is open. The battery gauge circuitry also includes a controller that initiates halting power delivery to a load if at least one of the switches is open. The controller also identifies the open switch.
    Type: Grant
    Filed: November 2, 2010
    Date of Patent: November 13, 2012
    Assignee: O2Micro International Limited
    Inventor: Constantin Bucur
  • Patent number: 8305013
    Abstract: A controller that monitors a rectified voltage and detects whether the rectified voltage comes from a TRIAC dimmer or an on/off switch dimmer is disclosed. The controller controls dimming of a light source according to the rectified voltage if the rectified voltage comes from the TRIAC dimmer. The controller controls dimming of the light source according to an operation of the on/off switch dimmer if the rectified voltage comes from the on/off switch dimmer.
    Type: Grant
    Filed: February 3, 2012
    Date of Patent: November 6, 2012
    Assignee: O2Micro International Limited
    Inventors: Yung Lin Lin, Ching-Chuan Kuo
  • Patent number: 8294424
    Abstract: An apparatus includes battery gauge circuitry implemented on an integrated circuit. The battery gauge circuitry includes a plurality of switches that individually open in response to a voltage reduction on a battery cell associated with a respective one of the switches. The battery gauge circuitry also includes a logic device that determines if at least one of the switches is open. The battery gauge circuitry also includes a register that stores data that indicates if at least one switch is open. The battery gauge circuitry also includes a controller that initiates halting power delivery to a load if at least one of the switches is open. The controller also identifies the open switch.
    Type: Grant
    Filed: November 2, 2010
    Date of Patent: October 23, 2012
    Assignee: O2Micro International Limited
    Inventor: Constantin Bucur
  • Patent number: 8261129
    Abstract: A method for diagnosing a control system for a stacked battery is disclosed. The control system comprises a plurality of processors, a plurality of controllers, and a monitoring unit (control unit). The method comprises sending a diagnostic information from the central unit to a top processor of the plurality of processors, transmitting a return information from the top processor of the plurality of processors to the central unit, comparing the diagnostic information sent from the central unit with the return information received by the central unit, and indicating a communication problem if the diagnostic information sent from the central unit is different from the return information received by the central unit. The steps are repeated by eliminating the top processor from a previous cycle and assigning a new top processor if there is no problem with the reconfigurable communication system.
    Type: Grant
    Filed: June 7, 2011
    Date of Patent: September 4, 2012
    Assignee: O2Micro International Ltd.
    Inventors: Guoxing Li, Xiaojun Zeng, Anquan Xiao, Xiaohua Hou
  • Patent number: 8237411
    Abstract: A monitoring circuit for accurately monitoring a voltage level from each of a plurality of battery cells of a battery pack includes an analog to digital converter (ADC) and a processor. The ADC is configured to accept an analog voltage signal from each of the plurality of battery cells and convert each analog voltage signal to a digital signal representative of an accurate voltage level of each battery cell. The processor receives such signals and provides a safety alert signal based on at least one of the signals. The ADC resolution may be adjustable. A balancing circuit provides a balancing signal if at least two of the digital signals indicate a voltage difference between two cells is greater than a battery cell balance threshold. An electronic device including such monitoring and balancing circuits is also provided. Various methods are also provided.
    Type: Grant
    Filed: April 13, 2010
    Date of Patent: August 7, 2012
    Assignee: O2Micro International Limited
    Inventors: Liusheng Liu, Guoxing Li
  • Patent number: 8239133
    Abstract: A global positioning system and dead reckoning (GPS&DR) integrated navigation system includes a GPS receiver coupled to a moving object for periodically generating GPS navigation information of said moving object, a DR system coupled to said moving object for periodically calculating DR navigation information of said moving object, and a filter coupled to said GPS receiver and said DR system for periodically calculating navigation information of said moving object, wherein said filter gets observation information by integrating said GPS navigation information and said DR navigation information according to a weight value of said GPS navigation information and a weight value of said DR navigation information, and calculates a current navigation information by integrating said observation information with previous navigation information from a plurality of previous cycles.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: August 7, 2012
    Assignee: O2Micro, International
    Inventors: James Wang, Xiaoguang Yu, Zhongbao Feng, Yiliang Liu, Shenghong Lu
  • Patent number: 8179053
    Abstract: A power supply system is provided for a multiple lamp LCD panel. In one aspect, the power supply includes a plurality of transformers for driving a plurality of respective CCFLs. The primary sides of each transformer are coupled in series to thereby reduce the stress on each transformer. For LCD panels that include longer CCFLs, a power supply is provided that includes a plurality of transformers for driving a plurality of respective CCFLs. The primary sides of each transformer are coupled in series and each lamp is coupled to two secondary sides of the transformers, thereby reducing the problems associated with longer CCFL tubes. In any of the embodiments, the power supply can be adapted to convert a high voltage DC signal to high voltage AC used to power the lamps.
    Type: Grant
    Filed: September 12, 2008
    Date of Patent: May 15, 2012
    Assignee: O2Micro International Limited
    Inventors: Yung-Lin Lin, Da Liu
  • Patent number: 8169249
    Abstract: In a signal monitoring system, a circuit includes an input terminal and an output terminal. In addition, a processor coupled to the circuit is operable for calculating a parameter indicative of an error factor of the circuit by setting a level difference between an input signal at the input terminal and an output signal at the output terminal to a predetermined level.
    Type: Grant
    Filed: September 23, 2011
    Date of Patent: May 1, 2012
    Assignee: O2Micro International Limited
    Inventors: Guoxing Li, Quanwang Liu, Shiqiang Liu, Juncai Hu
  • Patent number: 8165020
    Abstract: A network interface system for transferring a data packet between a host system and a network includes multiple matchers and multiple queues. The matchers match the data packet with multiple rules from the host system to generate multiple matching results and allocate a transferring priority to the data packet according to the rules. The queues correspond to the matchers respectively. A queue of the queues stores information indicating the transferring priority for the data packet according to the matching results and priorities of matchers.
    Type: Grant
    Filed: December 6, 2010
    Date of Patent: April 24, 2012
    Assignee: O2Micro International Limited
    Inventors: Jyshyang Chen, Chao Jiang
  • Patent number: 8164305
    Abstract: The present invention provides a battery circuit including a first battery cell with a first parameter having a first value and a second battery cell with a second parameter having a second value. The second battery cell is coupled to the first battery cell in series. The battery circuit further includes a magnetic device operable for storing energy transferred from the first battery cell via a first winding coupled to the first battery cell and for releasing the stored energy to the second battery cell via a second winding coupled to the second battery cell if the first value of the first parameter is greater than the second value of the second parameter.
    Type: Grant
    Filed: September 27, 2010
    Date of Patent: April 24, 2012
    Assignee: O2Micro International, Ltd.
    Inventors: Chutao Zhang, Songtao Chen