Patents by Inventor Lei Du

Lei Du 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: 8098018
    Abstract: The present invention provides a pulse dimming circuit and a method thereof. The pulse dimming circuit is compatible for both DC input signal and PWM input signal using only one circuit board, and includes a first input port, a second input port, a comparison signal generator, a comparator, a logic module, and a switch network electrically coupled to the second input port, an output terminal of the comparator, and an output terminal of the logic module.
    Type: Grant
    Filed: November 5, 2009
    Date of Patent: January 17, 2012
    Assignee: Monolithic Power Systems, Inc.
    Inventors: Bairen Liu, Lei Du, Yuancheng Ren
  • Publication number: 20110317777
    Abstract: Transmissions on a composite carrier including at least two component carriers can be controlled by means of a message by the provider of the carrier. The provider may receive a message from a device attempting to transmit on the composite carrier, and include in a response thereof an indication of at least one component carrier to be used by the device for a subsequent transmission. The device then received the message from the provider, and can determine based thereon at least one component carrier to be used by the device for at least one subsequent transmission, and transmit on the determined at least one component carrier.
    Type: Application
    Filed: February 18, 2009
    Publication date: December 29, 2011
    Inventors: Min Huang, Lei Du, Yong Teng
  • Publication number: 20110285301
    Abstract: Triac dimmer compatible switching mode power supplies used as LED drivers are disclosed herein. A PFC controller is configured in the switching mode power supplies. With the PFC controller, the current keeping the triac in the on-state is supplied by the DC/DC converter, and the LC resonance is reduced.
    Type: Application
    Filed: May 18, 2011
    Publication date: November 24, 2011
    Inventors: Naixing Kuang, Lei Du, Junming Zhang, Yuancheng Ren
  • Publication number: 20110267957
    Abstract: A communication system is presented, which is capable of sending a transmission over an interface having at least two aggregated component carriers including a primary component carrier and at least one secondary component carrier, wherein the primary component carrier has a physical downlink control channel (PDCCH) associated therewith and wherein the PDCCH is capable of signaling allocations for the primary component carrier and the at least one secondary component carrier. A method of operating a network element including sending to a user equipment a transmission indication indicative of the transmission in the PDCCH of the primary component carrier. A method of operating a user equipment includes monitoring downlink control signaling for a transmission indication indicative of a transmission to the user equipment only on the PDCCH of the primary component carrier.
    Type: Application
    Filed: January 7, 2009
    Publication date: November 3, 2011
    Inventors: Lei Du, Min Huang, Yong Teng
  • Publication number: 20110234122
    Abstract: Circuitry and methods for driving a plurality of LED strings are disclosed herein. In one embodiment, the circuitry comprises a plurality of current regulating circuits electrically coupled to the LED strings and are configured to regulate a current flowing through the LED strings. At least two control circuits are coupled to the current regulating circuits and are configured to generate a control signal according to terminal voltages of the corresponding current regulating circuits. A voltage converter is electrically coupled to the LED strings and to the at least two control circuits, and is configured to regulate the DC driving voltage according to the at least two control signals.
    Type: Application
    Filed: March 22, 2011
    Publication date: September 29, 2011
    Inventors: Bo Yu, Yuancheng Ren, Lei Du, Naixing Kuang, Zhishun Li
  • Publication number: 20110227497
    Abstract: Embodiments of LED driver circuits and the associated methods are disclosed herein. In one embodiment, the LED driver circuit comprises a switch-mode converter, a controller, a feedback circuit, and a gating circuit. The feedback circuit includes a current balance circuit. The gating circuit is responsive to both a current feedback signal and a voltage feedback signal and is configured to select one of them as the feedback signal.
    Type: Application
    Filed: March 15, 2011
    Publication date: September 22, 2011
    Inventors: Jin Hu, Lei Du, Yuancheng Ren, Junming Zhang, Zhijun Ye
  • Publication number: 20110227493
    Abstract: Light emitting diode (LED) dimming and driver systems and associated methods of control are disclosed herein. In one embodiment, a system comprises a PFC stage and an LED driver stage. The LED driver stage comprises an isolated converter and a controller responsive to a dimming signal to dim LED strings for backlight. The controller also regulates an output current of the isolated converter.
    Type: Application
    Filed: March 15, 2011
    Publication date: September 22, 2011
    Inventors: Lei Du, Bairen Liu, Kaiwei Yao, Junming Zhang, Yuancheng Ren
  • Publication number: 20110227492
    Abstract: LED driver systems and associated methods of control are disclosed herein. In one embodiment, the LED driver system comprises a converter and a controller. The controller is responsive to the LED current feedback signal and a dimming signal, and operable to generate a continuous gate drive signal to control the primary side switch of the converter. Thus, the controller regulates the output current of the converter.
    Type: Application
    Filed: March 15, 2011
    Publication date: September 22, 2011
    Inventors: Lei Du, Bairen Liu, Kaiwei Yao, Junming Zhang, Yuancheng Ren
  • Publication number: 20110199793
    Abstract: The present technology are directed to switching mode power supplies with primary side control. In one embodiment, the switching mode power supply provides an equivalent current signal which represents a load current. The equivalent current signal is then used to control a switching circuit in the switching mode power supply.
    Type: Application
    Filed: January 28, 2011
    Publication date: August 18, 2011
    Inventors: Naixing Kuang, Lei Du, Junming Zhang, Yuancheng Ren
  • Patent number: 7965651
    Abstract: The present invention has disclosed a method for setting an active period starting point for a User Equipment (UE) in a Discontinuous Reception (DRX) mode, comprising steps of: a base station calculating and storing a position of the active period starting point for the UE based on predetermined parameters, so as to transmit data to the UE in a corresponding active period; the UE receiving Radio Resource Control (RRC) configuration information from the base station, and detecting whether the DRX mode is configured in it or not; the UE calculating its active period starting point based on predetermined DRX parameters in the received RRC configuration information; the UE starting DRX based on the calculated active period starting point; and the UE continuously monitoring a channel, but not starting DRX, when detecting that the DRX mode has not been configured in it. The present invention has also disclosed an apparatus for setting an active period starting point for a UE in a DRX mode.
    Type: Grant
    Filed: December 23, 2008
    Date of Patent: June 21, 2011
    Assignee: NTT DoCoMo, Inc.
    Inventors: Lei Du, Lan Chen, Mikio Iwamura, Umesh Kadaba Anil
  • Publication number: 20110127925
    Abstract: The present technology is generally related to Triac dimmer compatible driving circuits and methods thereof. The present technology also provides an electronic transformer that is integrated in the Traic dimmer compatible driving circuit. In one embodiment, the electronic transformer detects the conduction angles of an output AC voltage from the Triac dimmer and converts said output AC voltage into a PWM DC voltage having a duty cycle regulated by said conduction angles. Said PWM DC voltage is then applied to a WLED driver for driving a WLED.
    Type: Application
    Filed: November 29, 2010
    Publication date: June 2, 2011
    Inventors: Yong Huang, Lei Du
  • Patent number: 7915833
    Abstract: An inverter comprising a low-side switching element in series with a first primary winding; a high-side switching element in series with a second primary winding, where the combination of the low-side switching element and first primary winding is connected in parallel with the combination of the high-side switching element and the second primary winding; and a clamping capacitor having one terminal connected to the first primary winding and having a second terminal connected to the second primary winding. Other embodiments are described and claimed.
    Type: Grant
    Filed: February 25, 2008
    Date of Patent: March 29, 2011
    Assignee: Monolithic Power Systems, Inc.
    Inventors: Wei Chen, Yuancheng Ren, Junming Zhang, Lei Du
  • Publication number: 20110062894
    Abstract: Methods and circuits for CCFL driving circuit control are disclosed according to various embodiments of the present disclosure. In certain embodiments, the methods and circuits for CCFL driving circuit control provide a control signal for regulating both the duty ratio and frequency of the switching control signal that controls the CCFL driving circuit. External components for control loop compensation and frequency sweeping rate, and/or striking frequency setting may also be utilized.
    Type: Application
    Filed: September 15, 2010
    Publication date: March 17, 2011
    Inventors: NAIXING KUANG, LEI DU, YUANCHENG REN
  • Patent number: 7907582
    Abstract: A method and an apparatus select an access point (AP) in a wireless LAN to associate or reassociate, based on considerations that take into account the quality-of-service (QoS) status of the stations (STAs) and the potential hidden terminal effect. The method utilizes advertised or requested information obtained from an AP which includes the QoS status in each basic service set (BSS) and estimates the potential hidden terminal (HT) effect based on local channel sensing by the STA. The method selects the AP in a manner that reduces the possibility of collision from equal and higher priority HTs, thus providing greater transmission throughput and improving performance.
    Type: Grant
    Filed: October 9, 2007
    Date of Patent: March 15, 2011
    Assignee: NTT DOCOMO, Inc.
    Inventors: Lei Du, Yong Bai, Lan Chen, Fujio Watanabe, Akira Yamada
  • Publication number: 20100302288
    Abstract: A dual ended driver circuit for a LCD backlight is disclosed. The circuit comprises a master board and a slave board, which provides a first output drive signal and a second output drive signal to either end of a lamp set, respectively. The circuit only uses one control chip to synchronize and make symmetrical the first output drive signal and the second output drive signal.
    Type: Application
    Filed: May 26, 2010
    Publication date: December 2, 2010
    Inventors: Yuancheng Ren, Jiali Cai, Lei Du, Junming Zhang, Eric Yang
  • Publication number: 20100270937
    Abstract: A circuit for controlling the switch frequency of an inverter that strikes and drives fluorescent lamps is disclosed. The circuit comprises a frequency generator and an offset circuit. The offset circuit provides a current signal in response to the lamp status. The frequency generator provides a frequency control signal in respond to the current signal so as to control the switch frequency of the inverter. When the lamp is open, the switch frequency of the inverter is higher; when the lamp is lighted, the switch frequency of the inverter is lower.
    Type: Application
    Filed: April 21, 2010
    Publication date: October 28, 2010
    Inventors: Junming Zhang, Jiali Cai, Lei Du, Yuancheng Ren, Eric Yang
  • Publication number: 20100259180
    Abstract: An LED circuit is disclosed. The circuit senses the average current flowing through the LED. The sensed signal is compensated and modulated. The modulated signal is then used to control the ON/OFF state of a switch that supplies power to the LED.
    Type: Application
    Filed: April 6, 2010
    Publication date: October 14, 2010
    Inventors: Yuancheng Ren, Lei Du, Yong Huang
  • Publication number: 20100141149
    Abstract: The present disclosure provides methods and apparatus for fault protection for electronic devices (e.g., cold cathode fluorescent lamps). In one embodiment, a fault signal is detected and compared with a threshold to output a comparison signal. The comparison signal is then processed to generate a trigger signal, which triggers a fault control block once it satisfies certain fault conditions.
    Type: Application
    Filed: December 9, 2009
    Publication date: June 10, 2010
    Inventors: Bairen Liu, Lei Du, Yuancheng Ren
  • Publication number: 20100117555
    Abstract: The present invention provides a pulse dimming circuit and a method thereof. The pulse dimming circuit is compatible for both DC input signal and PWM input signal using only one circuit board.
    Type: Application
    Filed: November 5, 2009
    Publication date: May 13, 2010
    Applicant: Monolithic Power Systems, Inc.
    Inventors: Bairen Liu, Lei Du, Yuancheng Ren
  • Publication number: 20100113051
    Abstract: A method for use of a RA preamble with multiple available RACH resources is described. The method includes allocating resources including a plurality of RACH resources for a UE. Information that indicates a dedicated preamble and the allocated resources is sent to the UE. The UE receives the information. A response including the dedicated preamble is generated at the UE. The method also includes the UE sending the response over at least two of the allocated resources. In response to receiving at least one response, a message is transmitted to the UE.
    Type: Application
    Filed: November 3, 2009
    Publication date: May 6, 2010
    Inventors: Lei Du, Min Huang, Yong Teng