Patents Assigned to O2Micro International
  • Patent number: 8154449
    Abstract: A global positioning system (GPS) system includes a clock module for providing multiple counter values at multiple time points. The GPS system also includes a system module coupled to the clock module. The system module is capable of obtaining a time value for each time point according to a set of signals from a signal source. The system module is further capable of calculating a set of parameters based on the counter values and the time value for each time point, and determining an estimated time value based on the parameters and a present counter value from the clock module.
    Type: Grant
    Filed: August 14, 2009
    Date of Patent: April 10, 2012
    Assignee: O2Micro International, Ltd.
    Inventors: Xiaoguang Yu, Yishao Max Huang, Haiquan Huang
  • Patent number: 8149164
    Abstract: A signal processing system for demodulating navigation bits from a satellite signal is disclosed herein. The signal processing system includes a digital baseband processor for determining a boundary between two navigation bits in the navigation bits according to a first plurality of coarse acquisition (C/A) codes captured from the satellite signals, storing the first plurality of C/A codes, and demodulating a second plurality of C/A codes captured after determining the boundary to recover a first series of the navigation bits. The signal processing system further includes a complementary demodulating unit coupled to the digital baseband processor for demodulating the first plurality of C/A codes to recover a second series of the navigation bits.
    Type: Grant
    Filed: December 30, 2009
    Date of Patent: April 3, 2012
    Assignee: O2Micro International, Ltd.
    Inventors: Xiaoguang Yu, Haiquan Huang, Jinghua Zou, Lin Li, Bo Yu, Weihua Zhang, Lie Lu
  • 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
  • Patent number: 8129982
    Abstract: A voltage sensing circuit includes a voltage divider and a voltage rectifier. The voltage divider divides a first output voltage on a first output voltage line to a first divided output voltage. The voltage divider comprises a first metal foil and a first capacitor. The first metal foil and the first output voltage line can form a first capacitive component. The first capacitive component is coupled in series with the first capacitor. The first capacitive component and the first capacitor can generate the first divided output voltage. The voltage rectifier is coupled to the voltage divider and can rectify the first divided output voltage to a sensing voltage indicative of the first output voltage.
    Type: Grant
    Filed: June 22, 2009
    Date of Patent: March 6, 2012
    Assignee: O2Micro International Limited
    Inventors: Youling Li, Yingpeng Hu, Xiaojun Wang
  • Patent number: 8125160
    Abstract: A method according to one embodiment may include providing power to at least one light source. The method of this embodiment may also include detecting the frequency of at least one vertical synchronization signal, among a plurality of different synchronization signals, and controlling the power to at least one light source based on, at least in part, the detected frequency of at least one vertical synchronization signal. Of course, many alternatives, variations, and modifications are possible without departing from this embodiment.
    Type: Grant
    Filed: October 6, 2009
    Date of Patent: February 28, 2012
    Assignee: O2Micro International Limited
    Inventors: Yung-Lin Lin, Yu-Cheng Chang
  • 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: 20110298425
    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: Application
    Filed: August 22, 2011
    Publication date: December 8, 2011
    Applicant: O2Micro International Limited
    Inventors: Liusheng Liu, Guoxing Li
  • Patent number: 8072378
    Abstract: A navigation system for detecting error on Doppler frequencies of a plurality of satellite signals measured by the navigation system is disclosed herein. The navigation system includes an offset calculator for calculating offsets of the Doppler frequencies of the satellite signals during a predetermined time period and calculating an average value of the offsets. The navigation system further includes an error detecting unit coupled to the offset calculator. The error detecting unit compares the offsets of the Doppler frequencies of the satellite signals with the average value of the offsets and determines whether the satellite signals are unavailable according to corresponding comparison results.
    Type: Grant
    Filed: June 2, 2010
    Date of Patent: December 6, 2011
    Assignee: O2Micro International, Ltd.
    Inventors: Xiaoguang Yu, Bo Yu, Xiaoyong He, Jinghua Zou
  • Publication number: 20110289239
    Abstract: According to one aspect there is disclosed an apparatus. The apparatus may include a first device.
    Type: Application
    Filed: August 10, 2010
    Publication date: November 24, 2011
    Applicant: O2MICRO INTERNATIONAL LIMITED
    Inventors: Xiaojun Zeng, Kevin Sheng
  • Patent number: 8049471
    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: August 17, 2010
    Date of Patent: November 1, 2011
    Assignee: O2Micro International Limited
    Inventors: Marian Niculae, Constantin Bucur, William L. Densham
  • Patent number: 8022669
    Abstract: A battery management system can include a battery having a plurality of cells, a plurality of devices coupled to the battery, and a control unit coupled to a first device of the devices. The devices can assess the statuses of the cells. The control unit can communicate with a destination device of the devices via a default path and can communicate with the destination device via a backup path if an undesirable condition occurs in the default path.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: September 20, 2011
    Assignee: O2Micro International Limited
    Inventor: Guoxing Li
  • Patent number: 8015452
    Abstract: The present invention provides a control system which is used for a stacked battery of a plurality of battery packs. Each battery pack has a plurality of battery cells coupled in series. The control system is capable of reconfiguring communication among the battery packs in the stacked battery, and comprises a plurality of processors, a plurality of controllers, and a monitoring unit. The processors are coupled to the battery packs. Two adjacent processors among the processors are able to communicate with each other though a first bus. The controllers are coupled to the battery packs. Two adjacent controllers among the controllers are able to communicate with each other through a second bus. The processors are capable of communicating with the controllers through a third bus. The monitoring unit is used for monitoring communications among the plurality of processors and communications among the plurality of controllers.
    Type: Grant
    Filed: August 31, 2010
    Date of Patent: September 6, 2011
    Assignee: O2Micro International, Ltd.
    Inventors: Guoxing Li, Xiaojun Zeng, Anquan Xiao, Xiaohua Hou
  • Patent number: 8004460
    Abstract: A positioning method using global positioning system (GPS) signal and digital broadcasting system (DBS) signal. The method includes detecting a presence status of the GPS signal through a signal detector in a receiver, detecting a presence status of the DBS signal through the signal detector, determining the signal strength of the GPS signal if the GPS signal is detected, determining the signal strength of the DBS signal if the DBS signal is detected, choosing one positioning mode among a plurality of positioning modes in a signal processing unit in the receiver based on signal presence status and the signal strength of a detected signal, and determining a location of the receiver based on the chosen positioning mode. The plurality of positioning modes includes standalone GPS mode, assisted GPS (AGPS) mode, assisted GPS positioning with DBS assist mode, DBS positioning with GPS assist mode, standalone DBS mode, and assist DBS mode.
    Type: Grant
    Filed: March 18, 2010
    Date of Patent: August 23, 2011
    Assignee: O2Micro International, Ltd.
    Inventors: You-Yuh Jack Shyr, Mingqiang Cheng, Cuichai Ji
  • Patent number: 8004246
    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 23, 2011
    Assignee: O2Micro International Limited
    Inventors: Liusheng Liu, Guoxing Li
  • Patent number: 7999554
    Abstract: Voltage translator circuitry may include a path including a first resistor, a current controlling device, and a second resistor coupled in series. The voltage translator circuitry may further include an operational amplifier having a positive supply terminal to accept a positive supply voltage and a negative supply terminal to accept a negative supply voltage, neither the positive or negative supply voltage at ground voltage. The first resistor may further be coupled to a positive terminal of the battery cell to be monitored. The operational amplifier may have an input coupled to a negative terminal of the battery cell to be monitored. The voltage translator circuitry may further include an output terminal coupled to a node of the path between the current controlling device and the second resistor. The output terminal may be configured to provide the ground referenced cell voltage for the battery cell.
    Type: Grant
    Filed: November 1, 2005
    Date of Patent: August 16, 2011
    Assignee: O2Micro International Limited
    Inventors: Constantin Bucur, Marian Niculae
  • Patent number: 7983301
    Abstract: A method to enhance a mobile device's ability to transmit short messages over a wireless communication network is provided. The method includes the steps for preprocessing a data according to it data type, fragmenting the data into a plurality of data segments if the data is larger than a predetermined size after being preprocessed and compressed, and transmitting the data segments from a sending terminal after encoding the data segments. The method also includes the steps of recombining the plurality of decoded data segments into a single data after receiving and decoding the data, and displaying the data as a single piece of data at a receiving terminal after decompressing and processing the data.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: July 19, 2011
    Assignee: O2Micro International, Ltd.
    Inventor: Cheng Li
  • Publication number: 20110121653
    Abstract: A system may include an electronic device configured to consume a supply current; an AC to DC adapter configured to be coupled to the electronic device, wherein the AC to DC adapter has a maximum rated output current; a battery configured to be coupled to the electronic device; DC to DC converter configured to be coupled to the battery and the electronic device; and a controller configured to couple the AC to DC adapter to the electronic device, the controller further configured to couple the DC to DC converter to the battery and the electronic device when the supply current exceeds the maximum rated output current of the AC to DC adapter.
    Type: Application
    Filed: May 18, 2010
    Publication date: May 26, 2011
    Applicant: O2MICRO INTERNATIONAL LIMITED
    Inventors: Alexandru Hartular, Laszlo Lipcsei, Marian Niculae, Constantin Spiridon
  • Patent number: 7936757
    Abstract: An apparatus for packet fragment reassembly includes a memory and a fragment processing block coupled to the memory. The memory caches information contained in the headers of a plurality of packet fragments, wherein the plurality of packet fragments are identified as belonging to a particular packet. The fragment processing block directly performs operations to each packet fragment according to the information cached in the memory and a predetermined standard, wherein the information cached in the memory is used to track whether all packet fragments associated with the particular packet have been received at the apparatus.
    Type: Grant
    Filed: February 27, 2009
    Date of Patent: May 3, 2011
    Assignee: O2Micro International Limited
    Inventors: Lida Zhang, Jy Chen
  • Patent number: 7936151
    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: May 3, 2011
    Assignee: O2Micro International Limited
    Inventors: Constantin Bucur, Marian Niculae
  • Publication number: 20110074839
    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: Application
    Filed: December 7, 2010
    Publication date: March 31, 2011
    Applicant: O2MICRO INTERNATIONAL LIMITED
    Inventors: Da Liu, Yung-Lin Lin