Patents by Inventor Wenkai Wu

Wenkai Wu 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: 9343962
    Abstract: One embodiment includes a power regulator system. The system includes a switch control stage configured to generate at least one activation signal based on a pulse-width modulation (PWM) signal and to control a respective at least one switch to generate an output voltage. The system also includes a feedback stage configured to generate the PWM signal based on a ramp signal and a feedback voltage that is based on the output voltage. The system further includes a ramp generator stage configured to adaptively generate the ramp signal based on the output voltage and based on the at least one activation signal.
    Type: Grant
    Filed: May 31, 2013
    Date of Patent: May 17, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Kuang-Yao Cheng, Hal Chen, Wenkai Wu, Weidong Zhu
  • Patent number: 9124177
    Abstract: Systems and devices for smooth light load operation in a DC/DC converter are presented. The disclosed systems and methods enable smooth discontinuous conduction mode (DCM)/continuous conduction mode (CCM) transition. The disclosed systems and methods of smooth light load operation in a DC/DC converter may also avoid the generation of sub-harmonics during light load operation. In an example embodiment, a rising ramp is used to control the ON time of the converter oscillator, while a falling ramp controls the OFF time. During DCM operation, the minimum value of the falling ramp is clamped. The clamping of the falling ramp ensures a substantially similar level of the error amplifier output in both CCM and DCM and avoids disturbances caused by a difference in the error amplifier outputs between the modes.
    Type: Grant
    Filed: August 10, 2010
    Date of Patent: September 1, 2015
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Weidong Zhu, Xuening Li, Hal Chen, Wenkai Wu
  • Publication number: 20140266112
    Abstract: One embodiment includes a power regulator system. The system includes a switch control stage configured to generate at least one activation signal based on a pulse-width modulation (PWM) signal and to control a respective at least one switch to generate an output voltage. The system also includes a feedback stage configured to generate the PWM signal based on a ramp signal and a feedback voltage that is based on the output voltage. The system further includes a ramp generator stage configured to adaptively generate the ramp signal based on the output voltage and based on the at least one activation signal.
    Type: Application
    Filed: May 31, 2013
    Publication date: September 18, 2014
    Inventors: KUANG-YAO CHENG, HAL CHEN, WENKAI WU, WEIDONG ZHU
  • Patent number: 8476880
    Abstract: One embodiment of the invention includes regulation voltage system for a power supply system. The system includes a current sense system configured to generate a sense signal that represents an output current of the power supply system that is supplied to a load. The system also includes a positive voltage droop controller configured to provide a regulation voltage to the power supply system, the positive voltage droop controller setting the regulation voltage to one of a predetermined fixed reference voltage or a variable reference voltage based on the sense signal. The variable reference voltage can be less than the predetermined fixed reference voltage.
    Type: Grant
    Filed: August 19, 2010
    Date of Patent: July 2, 2013
    Assignee: Texas Instruments Incorporated
    Inventors: Wei Dong, Xiao Xu, Wenkai Wu
  • Patent number: 8269570
    Abstract: Systems and devices for ripple reduction in a DC/DC converter are presented. The disclosed systems and methods enable ripple reduction in discontinuous conduction mode (DCM) operation. In DCM, the inductor current peak to peak ripple may be reduced based on the load current. To achieve the reduction of the inductor peak to peak current ripple, a digital counter is used to count the time between consecutive PWM pulses. The digital output of the counter is used to control the pulse width modulation. As the digital output of the counter increases, the PWM on-time decreases. Since the PWM pulse is demanded by the load in DCM mode, the peak to peak inductor ripple is modulated by the counter, or, in turn, modulated by the load current.
    Type: Grant
    Filed: August 3, 2010
    Date of Patent: September 18, 2012
    Assignee: Texas Instruments Incorporated
    Inventors: Xuening Li, Hal Chen, Weidong Zhu, Wenkai Wu
  • Patent number: 8174250
    Abstract: A ripple regulator for providing a pulse width modulation (PWM) signal for regulating an output voltage of a power converter switching stage. The regulator including a ripple circuit for providing a ripple voltage; a comparison circuit for comparing the ripple voltage to an output of an error amplifier; and a PWM circuit producing the PWM signal and receiving an output of the comparison circuit and a clock signal input, the clock signal input determining a first edge of the PWM signal and the output of said comparison circuit determining a second edge of the PWM signal.
    Type: Grant
    Filed: October 6, 2008
    Date of Patent: May 8, 2012
    Assignee: International Rectifier Corporation
    Inventors: Wenkai Wu, Ken Boyden, Rami Hamze
  • Publication number: 20120043946
    Abstract: One embodiment of the invention includes regulation voltage system for a power supply system. The system includes a current sense system configured to generate a sense signal that represents an output current of the power supply system that is supplied to a load. The system also includes a positive voltage droop controller configured to provide a regulation voltage to the power supply system, the positive voltage droop controller setting the regulation voltage to one of a predetermined fixed reference voltage or a variable reference voltage based on the sense signal. The variable reference voltage can be less than the predetermined fixed reference voltage.
    Type: Application
    Filed: August 19, 2010
    Publication date: February 23, 2012
    Inventors: WEI DONG, Xiao Xu, Wenkai Wu
  • Publication number: 20120038331
    Abstract: Systems and devices for smooth light load operation in a DC/DC converter are presented. The disclosed systems and methods enable smooth discontinuous conduction mode (DCM)/continuous conduction mode (CCM) transition. The disclosed systems and methods of smooth light load operation in a DC/DC converter may also avoid the generation of sub-harmonics during light load operation. In an example embodiment, a rising ramp is used to control the ON time of the converter oscillator, while a falling ramp controls the OFF time. During DCM operation, the minimum value of the falling ramp is clamped. The clamping of the falling ramp ensures a substantially similar level of the error amplifier output in both CCM and DCM and avoids disturbances caused by a difference in the error amplifier outputs between the modes.
    Type: Application
    Filed: August 10, 2010
    Publication date: February 16, 2012
    Applicant: Texas Instruments Incoporated
    Inventors: Wenkai Wu, Weidong Zhu, Hal Chen, Xuening Li
  • Publication number: 20120032748
    Abstract: Systems and devices for ripple reduction in a DC/DC converter are presented. The disclosed systems and methods enable ripple reduction in discontinuous conduction mode (DCM) operation. In DCM, the inductor current peak to peak ripple may be reduced based on the load current. To achieve the reduction of the inductor peak to peak current ripple, a digital counter is used to count the time between consecutive PWM pulses. The digital output of the counter is used to control the pulse width modulation. As the digital output of the counter increases, the PWM on-time decreases. Since the PWM pulse is demanded by the load in DCM mode, the peak to peak inductor ripple is modulated by the counter, or, in turn, modulated by the load current.
    Type: Application
    Filed: August 3, 2010
    Publication date: February 9, 2012
    Applicant: Texas Instruments Incorporated
    Inventors: Xuening Li, Hal Chen, Weidong Zhu, Wenkai Wu
  • Patent number: 8067927
    Abstract: A control circuit for a multi-phase converter including an analog front-end circuit for receiving and processing an output voltage and current of the converter circuits and an average output current; a digital circuit for producing an output voltage reference for setting a desired output voltage of the converter; and an error circuit for comparing the output voltage reference and a parameter related to said output voltage and current for generating control signals for controlling the converter circuits, said error circuit including an Analog to Digital Converter circuit, further comprising a digital PWM generation circuit controlled by said Analog to Digital converter circuit for generating digital control signals for controlling the converter circuits.
    Type: Grant
    Filed: July 10, 2007
    Date of Patent: November 29, 2011
    Assignee: International Rectifier Corporation
    Inventors: Wenkai Wu, George Schuellein
  • Patent number: D694571
    Type: Grant
    Filed: March 1, 2013
    Date of Patent: December 3, 2013
    Assignee: Whirlpool Corporation
    Inventors: Leif A. Norland, Wenkai Wu
  • Patent number: D713669
    Type: Grant
    Filed: March 1, 2013
    Date of Patent: September 23, 2014
    Assignee: Whirlpool Corporation
    Inventors: Leif A. Norland, Wenkai Wu
  • Patent number: D714582
    Type: Grant
    Filed: March 1, 2013
    Date of Patent: October 7, 2014
    Assignee: Whirlpool Corporation
    Inventors: Leif A. Norland, Wenkai Wu
  • Patent number: D720176
    Type: Grant
    Filed: March 1, 2013
    Date of Patent: December 30, 2014
    Assignee: Whirlpool Corporation
    Inventors: Leif A. Norland, Wenkai Wu
  • Patent number: D720199
    Type: Grant
    Filed: November 8, 2013
    Date of Patent: December 30, 2014
    Assignee: Whirlpool Corporation
    Inventors: Daniel V. Clements, Gilius A. Gaska, Jason S. Lind, Wenkai Wu
  • Patent number: D739169
    Type: Grant
    Filed: March 13, 2014
    Date of Patent: September 22, 2015
    Assignee: Whirlpool Corporation
    Inventors: Ben C. Shao, Wenkai Wu
  • Patent number: D751860
    Type: Grant
    Filed: March 5, 2015
    Date of Patent: March 22, 2016
    Assignee: Whirlpool Corporation
    Inventors: John W. McConnell, Wenkai Wu
  • Patent number: D755031
    Type: Grant
    Filed: February 13, 2015
    Date of Patent: May 3, 2016
    Assignee: Whirlpool Corporation
    Inventors: John W. McConnell, Patrick J. Schiavone, Wenkai Wu
  • Patent number: D757487
    Type: Grant
    Filed: February 13, 2015
    Date of Patent: May 31, 2016
    Assignee: Whirlpool Corporation
    Inventors: John W. McConnell, Wenkai Wu
  • Patent number: D757488
    Type: Grant
    Filed: March 5, 2015
    Date of Patent: May 31, 2016
    Assignee: Whirlpool Corporation
    Inventors: John W. McConnell, Wenkai Wu