Patents Assigned to O2Micro International
  • Patent number: 7808548
    Abstract: A method according to one embodiment includes coupling at least one power supply to a power bus comprised in a digital camera. The method of this embodiment may also include allocating power to at least one component of the digital camera by coupling at least one component to the power bus based on at least one power management priority rule. Of course, many alternatives, variations, and modifications are possible without departing from this embodiment.
    Type: Grant
    Filed: December 30, 2004
    Date of Patent: October 5, 2010
    Assignee: O2Micro International Limited
    Inventors: Vlad Popescu-Stanseti, Liusheng Liu, James Lam, Bruce S. Denning, Sterling Du
  • Patent number: 7804273
    Abstract: A selector circuit configured to select among a DC power source and a plurality of batteries for an electronic device. The selector circuit includes a first comparator configured to compare a first input signal representative of a voltage level of the DC power source with a first threshold level and provide a first output signal representative of a difference between the first input signal and the first threshold level, and a selector output circuit. The selector output circuit is configured to provide selector output signals that control selection among the DC power source and the plurality of batteries. The selector output circuit providing said selector output signals to select the DC source and deselect the plurality of batteries if the first output signal is representative of the voltage level of said DC power source being greater than the first threshold level.
    Type: Grant
    Filed: March 10, 2009
    Date of Patent: September 28, 2010
    Assignee: O2Micro International Limited
    Inventors: Vlad Popescu-Stanesti, Marian Niculae, Constantin Bucur
  • Patent number: 7804278
    Abstract: In one embodiment, a battery management system includes a charger controller for controlling a charging current of a battery according to a status of a load which is powered by the battery, and a counter coupled to the charger controller for determining a charging time according to such status. Advantageously, a first charging current is selected when the load is off. A second charging current that is less than the first charging current is selected when the load is on. Furthermore, a frequency of the counter is set to a first frequency when the load is off. The frequency is set to a second frequency that is less than the first frequency when the load is on.
    Type: Grant
    Filed: July 25, 2007
    Date of Patent: September 28, 2010
    Assignee: O2Micro International Ltd.
    Inventors: Stefan Maireanu, Chun Lu, Jianping Xu, Xiaohua Lei, Zhitong Lei, Yongqiang Yu
  • Patent number: 7797729
    Abstract: The invention provides a method for providing enhancements to a BIOS system without using replacement hardware in a microprocessor-based device. The microprocessor-based device boots from a BIOS procedure and interrupts the BIOS procedure to read information from an information module inserted to a information module reader connected to the microprocessor-based device. The information read from the information module is used to selectively alter the BIOS procedure.
    Type: Grant
    Filed: September 6, 2005
    Date of Patent: September 14, 2010
    Assignee: O2Micro International Ltd.
    Inventor: Shyh-Shin Lee
  • Patent number: 7791469
    Abstract: A method and system for tracking a portable device. A tracking system includes a portable device, a first Radio Frequency (RF) module, and a second RF module. The first Radio Frequency (RF) module is installed in the portable device for transmitting a wireless signal. The second RF module is used for receiving the wireless signal. When a received amplitude of the wireless signal that is received by the second RF module is less than a predetermined value, the second RF module generates an alert.
    Type: Grant
    Filed: October 11, 2006
    Date of Patent: September 7, 2010
    Assignee: O2Micro International Limited
    Inventors: Jiwei Chen, James Lam
  • Patent number: 7791313
    Abstract: A selector circuit configured to select among a DC power source and a plurality of batteries for an electronic device. The selector circuit is responsive to an output signal from an associated power management unit. The selector circuit is further configured to permit parallel operation of two or more of the batteries. The selector circuit may further act to independently verify power conditions and override instructions from the PMU in certain instances to enhance power supply safety and battery life such as by preventing inter battery current flow from a higher potential battery to a lower potential battery coupled in parallel.
    Type: Grant
    Filed: February 10, 2009
    Date of Patent: September 7, 2010
    Assignee: O2Micro International Limited
    Inventors: Vlad Popescu Stanesti, Marian Niculae, Constantin Bucur
  • Patent number: 7791314
    Abstract: A power supply topology according to one embodiment includes a first path coupled to a controllable DC power source, a second path coupled to a rechargeable battery, and a third path coupled to a system load, the three paths coupled to a common node. The topology may further include a unidirectional switch coupled to the first path and a selectively unidirectional switch coupled to the second path. The topology may further include a power management control circuit including a wake up circuit having a comparison circuit and an output decision circuit. Of course, many alternatives, variations, and modifications are possible without departing from this embodiment.
    Type: Grant
    Filed: March 25, 2008
    Date of Patent: September 7, 2010
    Assignee: O2Micro International Limited
    Inventors: Constantin Bucur, Vlad Mihail Popescu-Stanesti, Marian Niculae, Daryl Nees
  • Patent number: 7777425
    Abstract: A multi-lamp backlight system is disclosed. The multi-lamp backlight system includes a plurality of lamps, an inverter circuit and a current balance circuit. The inverter circuit is capable of converting a DC input signal to a pair of AC output signals, which have a 180 degree phase shift. The pair of AC output signals are delivered to the plurality of lamps. The current balance circuit is connected to the low voltage sides of the plurality of lamps for balancing the lamp currents.
    Type: Grant
    Filed: May 30, 2007
    Date of Patent: August 17, 2010
    Assignee: O2Micro International Limited
    Inventors: Houng-Kuo Hsu, Chu-Chang Chen, Ching-Chuan Kuo
  • 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
  • Patent number: 7772882
    Abstract: A system for FPGA (Field Programmable Gate Array) upgrade includes: an FPGA, a FLASH memory and a CPLD. The FLASH memory includes a first section configured to store a workable version of bit files for the FPGA and a second section configured to store a backup version of bit files for the FPGA. The CPLD is coupled to the FPGA and the FLASH memory. The CPLD is configured to download the bit files from the FLASH memory to the FPGA to provide the FPGA with functionality. As a result, the CPLD communicates with CPU to upgrade the bit files in the FLASH memory, and indicates to the CPU which version of bit files has been downloaded to the FPGA.
    Type: Grant
    Filed: June 23, 2008
    Date of Patent: August 10, 2010
    Assignee: O2Micro International Limited
    Inventors: Licai Fang, Lin Gan, Shunguang Ding, Jyshyang Chen
  • Patent number: 7768806
    Abstract: A DC/AC inverter and method thereof are disclosed. The DC/AC inverter for driving a load includes a DC power supply for supplying a DC input voltage, a converter circuit coupled to the DC power supply which converts the DC input voltage into an AC signal used to drive the load, and a control circuit coupled to the converter circuit which sets a frequency of the AC signal. The control circuit is further capable of operating the DC/AC inverter in a fixed frequency mode and in a variable frequency mode in accordance with the DC input voltage and the load condition.
    Type: Grant
    Filed: December 11, 2006
    Date of Patent: August 3, 2010
    Assignee: O2Micro International Limited
    Inventors: Yung-Lin Lin, Da Liu
  • Patent number: 7769359
    Abstract: An adaptive wireless receiver and method thereof is disclosed in the present invention. The receiver includes an antenna, a bandpass filter, a front-end unit and a demodulator. Elements inside the front-end unit can be reused when the receiver operates in a zero intermediate frequency (ZIF) mode and in a low intermediate frequency (LIF) mode. The front-end unit includes a first and second down-conversion mixer, an analog filter, a first and second analog-to-digital converter (ADC), and a digital filter.
    Type: Grant
    Filed: May 23, 2007
    Date of Patent: August 3, 2010
    Assignee: O2Micro International Ltd.
    Inventors: Dong Feng, Jiwei Chen
  • Patent number: 7764021
    Abstract: A method according to one embodiment may include supplying ignition power and steady state power to at least one lamp. The method of this embodiment may also include receiving, during an ignition period of said lamp, a feedback signal indicative of power supplied to said lamp; comparing said feedback signal to a signal that is approximately equal to a signal indicative of steady state power; and maintaining a supply of ignition power to said lamp while said feedback signal remains below said signal indicative of said steady state power. Of course, many alternatives, variations, and modifications are possible without departing from this embodiment.
    Type: Grant
    Filed: April 14, 2005
    Date of Patent: July 27, 2010
    Assignee: O2Micro International Limited
    Inventors: Da Liu, Sheng Tai Lee, Ching Chuan Kuo
  • Publication number: 20100171467
    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: Application
    Filed: March 23, 2010
    Publication date: July 8, 2010
    Applicant: O2MICRO INTERNATIONAL LIMITED
    Inventors: Constantin Bucur, Marian Niculae
  • Publication number: 20100171502
    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: Application
    Filed: March 23, 2010
    Publication date: July 8, 2010
    Applicant: O2MICRO INTERNATIONAL LIMITED
    Inventors: Constantin Bucur, Marian Niculae
  • Patent number: 7737662
    Abstract: A power system for managing charging, discharging and protection of rechargeable batteries is disclosed. The power system mainly includes a power system. The power system includes a switching circuit coupled to the rechargeable batteries to charge and discharge the rechargeable batteries. The power system includes a power management unit to control the switching circuit. The power system includes a temperature sensing circuit to monitor a temperature of the batteries, voltage detectors to monitor voltages of the batteries, and current detectors to monitor a current of the batteries. If an abnormal condition is sensed by the power management unit when the power system is in an operating mode, the power management unit will terminate the operating mode by switching off the switching circuit to protect the batteries and the power system.
    Type: Grant
    Filed: December 26, 2006
    Date of Patent: June 15, 2010
    Assignee: O2Micro International Ltd.
    Inventors: Chun Lu, Stefan Maireanu, Luyang Luo, Lin Tang, Mingzhi He, Jianping Xu
  • Patent number: 7724553
    Abstract: A DC-to-DC converter with improved transient response, accuracy and stability is disclosed. The DC-to-DC converter includes a comparator, a driver, at least one switch and a stability circuit. The stability circuit receives a voltage signal based upon sensing one of the at least one switch. The configuration with elimination a current sensing resistor can create a simpler solution for the DC-to-DC converter.
    Type: Grant
    Filed: June 11, 2007
    Date of Patent: May 25, 2010
    Assignee: O2Micro International Ltd.
    Inventors: Footshen Wong, Laszlo Lipcsei, Sheng Huang
  • Patent number: 7719247
    Abstract: A DC/DC converter includes a switch, an inductor, a capacitor, a resistor, and a voltage divider. The switch is coupled to the input voltage. The inductor is used for coupling the first switch to an output node of the DC/DC converter so as to generate the output voltage at the output node. The capacitor is coupled to the output voltage. The resistor is coupled to the capacitor in series, and is coupled to ground. The voltage divider is coupled across the capacitor so as to reduce the zero frequency of the DC/DC converter.
    Type: Grant
    Filed: September 29, 2008
    Date of Patent: May 18, 2010
    Assignee: O2Micro International Limited
    Inventors: Laszlo Lipcsei, Sorin Hornet
  • Patent number: 7719211
    Abstract: A method according to one embodiment may include generating AC voltage and current and a striking voltage. The method of this embodiment may also include generating striking voltage and steady-state voltage for at least two lamp loads. The method of this embodiment may also include coupling at least two lamp loads in parallel. The method of this embodiment may also include coupling current balancing circuitry to the at least two lamp loads and providing, by the current balancing circuitry simultaneous striking voltage to the at least two lamps loads. The method of this embodiment may also include balancing, by the current balancing circuitry, AC current through the at least two lamp loads. Of course, many alternatives, variations, and modifications are possible without departing from this embodiment.
    Type: Grant
    Filed: May 13, 2008
    Date of Patent: May 18, 2010
    Assignee: O2Micro International Limited
    Inventors: Ching Chuan Kuo, Houng Kuo Hsu
  • Patent number: 7719236
    Abstract: A portable electrical device may include a DC to DC converter coupled to a common node, a load coupled to the common node, and a controller configured to control the DC to DC converter. The DC to DC converter may be configured to provide a charging current to a rechargeable battery from an adapter when the controller operates said DC to DC converter in a first adapter supply mode. The DC to DC converter may be configured to provide a battery supply current to the load via the common node when the controller operates the DC to DC converter in a second adapter supply mode. The adapter supply current and the battery supply current may add together at the common node to simultaneously provide a load supply current to the load in the second adapter supply mode.
    Type: Grant
    Filed: November 18, 2005
    Date of Patent: May 18, 2010
    Assignee: O2Micro International Limited
    Inventor: Alexandru Hartular