Patents Assigned to iWatt, Inc.
  • Publication number: 20150222173
    Abstract: A power converter with fast discharging to adapt to a load disconnect. The power converter comprises a magnetic component coupled between an input of the power converter and an output of the power converter. The magnetic component includes a primary winding and a secondary winding. A switch controls transfer of energy from the primary winding to the secondary winding according to on and off times of the switch. A discharge circuit is coupled to the output of the power converter. The discharge circuit is adapted to receive a signal indicative of whether the load is disconnected and to decrease an output voltage at the output of the power converter based on the signal indicative of whether the load is disconnected.
    Type: Application
    Filed: February 6, 2014
    Publication date: August 6, 2015
    Applicant: iWatt Inc.
    Inventor: Andrey Malinin
  • Publication number: 20150124494
    Abstract: The embodiments herein describe a switched mode power converter. In particular, the embodiments herein disclose techniques for adaptive synchronous rectification control. The switched mode power supply includes a synchronous rectifier controller that determines when to turn off the synchronous rectifier during each switching cycle based on a reference signal corresponding to when substantially all the power stored in a transformer of the power supply has been delivered to an electronic load. The synchronous rectifier controller may determine whether to adjust the reference signal used by the synchronous rectifier controller to turn off the synchronous rectifier during subsequent switching cycles.
    Type: Application
    Filed: November 1, 2013
    Publication date: May 7, 2015
    Applicant: iWatt Inc.
    Inventor: Andrey B. Malinin
  • Publication number: 20140268915
    Abstract: The embodiments herein describe a switched mode power converter. In particular, the embodiments herein disclose a method for powering a synchronous rectifier controller that enables synchronous rectification in the switched mode power converter. The synchronous rectifier controller may be enabled by a regulator circuit or directly from the output voltage.
    Type: Application
    Filed: March 14, 2013
    Publication date: September 18, 2014
    Applicant: IWATT INC.
    Inventors: Pengju Kong, Jianming Yao
  • Publication number: 20140268919
    Abstract: A primary-only power supply enables transmission of a signal or message from the secondary side of an isolated power supply to the primary side. To enable robust detection of the message without interfering with primary side sensing for output regulation, a configurable impedance current path is configured between the primary winding and ground. The primary side controller controls the configurable impedance current path to have a relatively low impedance during the normal mode and a relatively high impedance during the messaging mode.
    Type: Application
    Filed: October 1, 2013
    Publication date: September 18, 2014
    Applicant: iWatt Inc.
    Inventors: Jianming Yao, Pengju Kong, Yong Li, Junjie Zheng
  • Publication number: 20140210357
    Abstract: A LED lighting system, such as a dimmable LED lamp, that may simulate the performance of an incandescent bulb. LED strings of different colors may be connected to the output of a single LED driver that regulates an overall intensity of light produced by the LED lighting system. The color of the LED lighting system may be controlled by circuitry, such as one or more switches, that allocates current between the LED strings to change the color temperature of light emitted by the LED lighting system as the light intensity changes.
    Type: Application
    Filed: January 25, 2013
    Publication date: July 31, 2014
    Applicant: IWATT INC.
    Inventors: Liang Yan, Junjie Zheng
  • Publication number: 20140159486
    Abstract: Embodiments disclosed herein describe the use of two inductors in a non-isolated power converter. The power converter receives power from a non-regulated power source, and converts the received power to regulated output signals. Each inductor in the power converter receives power provided from the non-regulated power source via a switch controlled by a controller, and provides a regulated output to a power converter load. A first regulated output provided by a first inductor can be representative of a second regulated output provided by a second inductor. In addition, a voltage feedback signal can be provided for use by the controller based on the first regulated output and/or the second regulated output.
    Type: Application
    Filed: March 13, 2013
    Publication date: June 12, 2014
    Applicant: iWatt Inc.
    Inventor: Xiaolin Gao
  • Publication number: 20140160810
    Abstract: A switching power converter provides a communication link between a secondary side and a primary side of the switching power converter. During a messaging mode, the communication link enables information to be transmitted from an electronic device coupled to the secondary side to a controller on the primary side. The communication link may be used to transmit operating parameters related to powering the electronic device. The switching power converter may then adapt its switching operation to achieve different regulated output voltage and/or current to accommodate the detected electronic device.
    Type: Application
    Filed: December 11, 2012
    Publication date: June 12, 2014
    Applicant: iWatt Inc.
    Inventor: Junjie Zheng
  • Publication number: 20140159616
    Abstract: A TRIAC dimmer controller for an LED lamp dynamically adjusts the amount of additional current supplied to the TRIAC dimmer based on the TRIAC dimmer operating mode. A TRIAC dimmer current controller continually senses the TRIAC dimmer current loading and determines a TRIAC dimmer operating mode based on the detected current. The TRIAC dimmer controller compares the detected current with a threshold current value called a TRIAC holding current, and adjusts the amount of bleeder current based on the difference between the detected current and the threshold current value. By continually sensing the TRIAC dimmer current loading, the LED controller regulates the amount of bleeder current supplied to the TRIAC dimmer using a single sink current path to satisfy the TRIAC dimmer current demands of multiple TRIAC dimmer operating modes.
    Type: Application
    Filed: December 8, 2013
    Publication date: June 12, 2014
    Applicant: iWatt Inc.
    Inventors: XIAOYAN WANG, CHENGLONG ZHANG, GUANG FENG, CLARITA KNOLL, CHUANYANG WANG, JIANG CHEN, LIANG YAN, DICKSON T. WONG
  • Publication number: 20140153292
    Abstract: The embodiments disclosed herein describe a method of a controller to maintain a substantially constant average output current at the output of a switching power converter. In one embodiment, the controller uses a regulation voltage that corresponds to the primary peak current regulation level to regulate the average output current.
    Type: Application
    Filed: December 5, 2012
    Publication date: June 5, 2014
    Applicant: IWATT INC.
    Inventors: Liang Yan, John William Kesterson, Xiaoyan Wang, Guang Feng, Clarita Poon
  • Publication number: 20140103838
    Abstract: An LED lamp is provided in which the output light intensity of the LEDs in the LED lamp is adjusted based on the input voltage to the LED lamp. A dimmer control unit detects a type of dimmer switch during a configuration process. Using the detected dimmer type, the dimmer control unit generates control signals appropriate for the detected dimmer type to provide regulated current to the LEDs and to achieve the desired dimming effect. The LED lamp can be a direct replacement of conventional incandescent lamps in typical wiring configurations found in residential and commercial building lighting applications that use conventional dimmer switches.
    Type: Application
    Filed: December 19, 2013
    Publication date: April 17, 2014
    Applicant: iWatt Inc.
    Inventors: Junjie Zheng, John W. Kesterson, Richard M. Myers, Baorong Chen, Gordon Chen
  • Publication number: 20140085941
    Abstract: A power converter includes a transformer with a primary and a secondary winding and a switch. A controller of the power converter at the primary winding side of the transformer generates a control signal to turn on or turn off the switch, the switch being turned on responsive to the control signal being in a first state and the switch being turned off responsive to the control signal being in a second state. The controller determines current through the primary winding generated while the switch is turned on and indirectly detects an input voltage to the power converter based on the current through the primary winding generated while the switch is turned on. The controller in turn may detect conditions such as a loss of power or brown out at the input of the power converter based on the indirectly detected input voltage.
    Type: Application
    Filed: September 23, 2013
    Publication date: March 27, 2014
    Applicant: iWatt Inc.
    Inventors: Yong Li, Hien Huu Bui, David Nguyen, Fuqiang Shi
  • Publication number: 20140085940
    Abstract: A controller of a switching power converter includes a voltage protection circuit that generates a modified supply voltage that does not exceed a predetermined threshold voltage to power one or more components of the controller.
    Type: Application
    Filed: September 19, 2013
    Publication date: March 27, 2014
    Applicant: iWatt Inc.
    Inventors: Andrew Kwok-Cheung Lee, Jiang Chen, Yong Li
  • Publication number: 20140085938
    Abstract: The embodiments herein include a primary-side controller for a switching power converter that is capable of receiving a detection signal from a secondary-side detection circuit indicating that an output voltage has reached a condition. The controller determines the appropriate action once a detection signal has been received by distinguishing whether a dynamic load condition has been placed on the power supply versus other operating conditions.
    Type: Application
    Filed: September 23, 2013
    Publication date: March 27, 2014
    Applicant: iWatt Inc.
    Inventors: Fuqiang Shi, Yong Li, Mengfei Liu
  • Publication number: 20140078789
    Abstract: A power converter includes a transformer with a primary and a secondary winding. Feedback and control is maintained on the primary-side while a separate load detection circuit detects dynamic load conditions on the secondary-side. The load detection circuit detects dynamic load conditions at the time when a load is connected to the output of the switching power converter and, in turn, generates an alert signal. A coupling circuit coupled to the load detection circuit at the secondary winding side of the transformer and to the controller at the primary winding side of the transformer transmits the alert signal to the controller. The controller regulates the output voltage based on the feedback signal generated at the primary side of the transformer while detecting and responding to the dynamic load condition based on the alert signal generated at the secondary side of the transformer.
    Type: Application
    Filed: September 18, 2013
    Publication date: March 20, 2014
    Applicant: iWatt Inc.
    Inventors: Yong Li, Jiang Chen, Junjie Zheng, Jianming Yao, Xiaolin Gao
  • Publication number: 20140036549
    Abstract: A secondary-side dynamic load detection system and method rapidly identifies when a dynamic load has been placed on the output (e.g., when an electronic device is re-connected to the switching power converter). Once a dynamic load condition has been detected by the secondary side detector, a dynamic load detection signal is communicated from the secondary side of the switching power converter to a switch controller on the primary side. The switch controller can then quickly adapt switching in response to the dynamic load condition.
    Type: Application
    Filed: July 31, 2012
    Publication date: February 6, 2014
    Applicant: IWATT INC.
    Inventor: Yong Li
  • Patent number: 8643303
    Abstract: An LED lamp is provided in which the output light intensity of the LEDs in the LED lamp is adjusted based on the input voltage to the LED lamp. A dimmer control unit detects a type of dimmer switch during a configuration process. Using the detected dimmer type, the dimmer control unit generates control signals appropriate for the detected dimmer type to provide regulated current to the LEDs and to achieve the desired dimming effect. The LED lamp can be a direct replacement of conventional incandescent lamps in typical wiring configurations found in residential and commercial building lighting applications that use conventional dimmer switches.
    Type: Grant
    Filed: June 13, 2012
    Date of Patent: February 4, 2014
    Assignee: iWatt Inc.
    Inventors: Junjie Zheng, John W. Kesterson, Richard M. Myers, Baorong Chen, Gordon Chen
  • Publication number: 20140022829
    Abstract: The embodiments disclosed herein describe a method of a controller of a switching power converter that provides a configurable power factor control method for the switching power converter. In one embodiment, the controller combines power regulation control methods of constant on-time control and constant power control to adjust the power factor of the switching power converter.
    Type: Application
    Filed: July 18, 2012
    Publication date: January 23, 2014
    Applicant: IWATT, INC.
    Inventors: Fuqiang Shi, Xiaolin Gao, Hien Huu Bui, Yong Li, John William Kesterson
  • Publication number: 20140015447
    Abstract: Embodiments disclosed herein describe the use of a power supply to provide power to an LED load. The power supply provides a present output current to the LED, and receives a temperature signal representing the operating temperature of the LED. A target output current is determined, for instance based on the temperature signal. An output current rate of change is determined, and the power supply adjusts the output current to the LED at the determined rate of change until the output current is substantially equal to the target current.
    Type: Application
    Filed: March 13, 2013
    Publication date: January 16, 2014
    Applicant: iWatt Inc.
    Inventors: Fuqiang Shi, Qiu Sha, Xiaolin Gao, Gordon Chen
  • Publication number: 20130314454
    Abstract: Selective dimming in a light emitting display device to reduce power consumption. The display device includes a display panel that includes a plurality of light emitting pixels. An image processor is configured to divide an image frame into a plurality of regions and to reduce pixel intensity levels in at least one region of the plurality of regions to generate an adjusted image frame. The at least one region corresponds to a background of the image frame. A display driver converts data for the adjusted image frame into control signals for controlling brightness of the light emitting pixels. The display device may be, for example, an organic light emitting diode (OLED) display device or other type of display device that includes light emitting pixels.
    Type: Application
    Filed: May 9, 2013
    Publication date: November 28, 2013
    Applicant: iWatt Inc.
    Inventors: Xuecheng Jin, Gyan Tiwary
  • Publication number: 20130314391
    Abstract: A Predictive Power Control (PPC) device within a TCON Bias IC that addresses an overdesign inefficiency and enables a low cost solution. A PPC block utilizes the next frame image data and interacts with a pulse width modulation (PWM) control block of internal regulators to proactively prepare the output voltages of a power regulator for the power requirements in one or more future frames, for example.
    Type: Application
    Filed: May 23, 2012
    Publication date: November 28, 2013
    Applicant: IWATT INC.
    Inventor: Xuecheng Jin