Patents by Inventor Xuecheng Jin

Xuecheng Jin 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: 9564085
    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: Grant
    Filed: May 9, 2013
    Date of Patent: February 7, 2017
    Assignee: Dialog Semiconductor Inc.
    Inventors: Xuecheng Jin, Gyan Tiwary
  • Patent number: 9451664
    Abstract: An adaptive switch mode LED driver provides an intelligent approach to driving multiple strings of LEDs. The LED driver determines an optimal current level for each LED channel from a limited set of allowed currents. The LDO driver then determines a PWM duty cycle for driving the LEDs in each LED channel to provide precise brightness control over the LED channels. Beneficially, the LED driver minimizes the power dissipation in the LDO circuits driving each LED string, while also ensuring that the currents in each LED string are maintained within a limited range. A sample and hold LDO allows PWM control over extreme duty cycles with very fast dynamic response. Furthermore, fault protection circuitry ensures fault-free startup and operation of the LED driver.
    Type: Grant
    Filed: November 13, 2012
    Date of Patent: September 20, 2016
    Assignee: Dialog Semiconductor Inc.
    Inventors: Xuecheng Jin, Yu Cheng Chang, Yang Li, Maofeng Lan, John W. Kesterson, Xiaoyan Wang, Chenghung Pan
  • Patent number: 9239816
    Abstract: A method of power system preventive control candidate measures identification self-adaptive to external environment, which is applicable to dynamic identification of stations and power equipment under the effect of calamity, and judgment of preventive control measures that lose or restore control capability, and those for which control range or cost has changed. Automatic online identification of set of preventive control candidate measures includes two tasks: identification of stations and power equipment under the effect of calamity, and adjustment of the space of preventive control measures.
    Type: Grant
    Filed: October 17, 2011
    Date of Patent: January 19, 2016
    Assignees: JIANGXI ELECTRIC POWER COMPANY, STATE GRID ELECTRIC POWER RESEARCH INSTITUTE
    Inventors: Xuecheng Jin, Haohao Wang, Zhuxiang Yao, Taishan Xu, Genhua Zou, Bijun Li, Jianhua Xiong, Wei Xu, Feng Wen, Huimin Peng
  • Patent number: 9224340
    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: Grant
    Filed: May 23, 2012
    Date of Patent: December 29, 2015
    Assignee: Dialog Semiconductor Inc.
    Inventor: Xuecheng Jin
  • Patent number: 9161402
    Abstract: An LED driver controls current through an LED string. The LED driver generates a boosted PWM signal to drive a PWM transistor in the LED current path such that the PWM transistor maintains a substantially constant VGS, thus minimizing turn-on impedance of the PWM transistor. A current mirror circuit controls peak LED current when the PWM transistor is on. A trimming circuit includes a set of programmable switches to couple or decouple trimming transistor from the LED current path, and allowing for fine calibration of the LED current. By maintaining a low resistance and compensating for current mismatch in the LED current path, the LED driver provides efficient power performance and robustness that is particularly beneficial in high current applications.
    Type: Grant
    Filed: March 31, 2014
    Date of Patent: October 13, 2015
    Assignee: Dialog Semiconductor Inc.
    Inventors: Minjong Kim, Enzhu Liang, Xuecheng Jin
  • Publication number: 20140210365
    Abstract: An LED driver controls current through an LED string. The LED driver generates a boosted PWM signal to drive a PWM transistor in the LED current path such that the PWM transistor maintains a substantially constant VGS, thus minimizing turn-on impedance of the PWM transistor. A current mirror circuit controls peak LED current when the PWM transistor is on. A trimming circuit includes a set of programmable switches to couple or decouple trimming transistor from the LED current path, and allowing for fine calibration of the LED current. By maintaining a low resistance and compensating for current mismatch in the LED current path, the LED driver provides efficient power performance and robustness that is particularly beneficial in high current applications.
    Type: Application
    Filed: March 31, 2014
    Publication date: July 31, 2014
    Applicant: Dialog Semiconductor Inc.
    Inventors: Minjong Kim, Enzhu Liang, Xuecheng Jin
  • Patent number: 8791647
    Abstract: A system controls a switching power converter to power LED strings using a predictive feedforward control mechanism. An LED controller determines programmed current levels and duty cycles for driving LED strings. The LED controller determines a predicted load for a subsequent cycle of a switching power converter driving the LED strings based on the programmed current levels and duty cycles. A power conversion controller uses the predicted load information to control switching of the switching power converter. This improves the dynamic response of the switching converter to changing load conditions, thereby improving overall power efficiency and performance of the system.
    Type: Grant
    Filed: December 28, 2011
    Date of Patent: July 29, 2014
    Assignee: Dialog Semiconductor Inc.
    Inventors: John William Kesterson, Xiaoyan Wang, Xuecheng Jin, Enzhu Liang, Selcuk Sen
  • Patent number: 8710752
    Abstract: A system that provides an intelligent approach to driving multiple strings of LEDs. A processing device determines an optimal current level for each LED string from a limited set of allowed currents. The processing device also determines a PWM duty cycle for driving the LEDs in each LED string to provide precise brightness control over the LED string. The settings for the current level and duty cycle are transmitted to an LED driver for regulating the current and on-off times of the LED strings. Beneficially, the system reduces the size of the LED driver while leveraging existing resources available in the processing device to operate the LEDs in a power efficient manner.
    Type: Grant
    Filed: March 3, 2011
    Date of Patent: April 29, 2014
    Assignee: Dialog Semiconductor Inc.
    Inventors: Xuecheng Jin, Minjong Kim, Enzhu Liang, John William Kesterson, Xiaoyan Wang
  • Patent number: 8710753
    Abstract: An LED driver controls current through an LED string. The LED driver generates a boosted PWM signal to drive a PWM transistor in the LED current path such that the PWM transistor maintains a substantially constant VGS, thus minimizing turn-on impedance of the PWM transistor. A current mirror circuit controls peak LED current when the PWM transistor is on. A trimming circuit includes a set of programmable switches to couple or decouple trimming transistor from the LED current path, and allowing for fine calibration of the LED current. By maintaining a low resistance and compensating for current mismatch in the LED current path, the LED driver provides efficient power performance and robustness that is particularly beneficial in high current applications.
    Type: Grant
    Filed: December 7, 2011
    Date of Patent: April 29, 2014
    Assignee: Dialog Semiconductor Inc.
    Inventors: Minjong Kim, Enzhu Liang, Xuecheng Jin
  • Publication number: 20140009510
    Abstract: A light emitting display device with backlight dimming compensation. A backlight emits light based on a backlight control signal. A power supply generates a first supply voltage based on a supply control signal. A data driver converts pixel data into analog data voltages. A dynamic voltage range of the analog data voltages is controlled by the first supply voltage. A pixel array includes a plurality of pixels, and transparency of the pixels to the light emitted by the backlight is based on the analog data voltages. A power control module of the display device determines if a power condition is met and, responsive to the power condition being met, adjusts the backlight control signal to reduce a brightness of light emitted by the backlight and adjusts the supply control signal to increase the first supply voltage.
    Type: Application
    Filed: June 18, 2013
    Publication date: January 9, 2014
    Inventor: Xuecheng Jin
  • 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
  • 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
  • Patent number: 8581568
    Abstract: A start-up circuit in a switch-mode power converter that employs a Zener diode to provide a reference voltage to reduce the power consumption and the size of the start-up circuit. The start-up circuit also includes a coarse current source and a coarse reference voltage signal generator for producing current and reference voltage for initial startup operation of a bandgap circuit. The reference signal and current from coarse current source and the reference voltage signal generator are subject to large process, voltage and temperature (PVT) variations or susceptible to noise from the power supply, and hence, these signals are used temporarily during start-up and replaced with signals from higher performance components. After bandgap circuit becomes operational, the start-up receives voltage reference signal from the bandgap circuit to more accurately detect undervoltage lockout conditions.
    Type: Grant
    Filed: October 19, 2010
    Date of Patent: November 12, 2013
    Assignee: iWatt Inc.
    Inventors: Enzhu Liang, Jiang Chen, Xuecheng Jin
  • Publication number: 20130246000
    Abstract: A method of power system preventive control candidate measures identification self-adaptive to external environment, which is applicable to dynamic identification of stations and power equipment under the effect of calamity, and judgment of preventive control measures that lose or restore control capability, and those for which control range or cost has changed. Automatic online identification of set of preventive control candidate measures includes two tasks: identification of stations and power equipment under the effect of calamity, and adjustment of the space of preventive control measures.
    Type: Application
    Filed: October 17, 2011
    Publication date: September 19, 2013
    Applicants: State Grid Electric Power Research Institute, Jiangxi Electric Power Company
    Inventors: Xuecheng Jin, Haohao Wang, Zhuxiang Yao, Taishan Xu, Genhua Zou, Bijun Li, Jianhua Xiong, Wei Xu, Feng Wen, Huimin Peng
  • Publication number: 20130169172
    Abstract: A system controls a switching power converter to power LED strings using a predictive feedforward control mechanism. An LED controller determines programmed current levels and duty cycles for driving LED strings. The LED controller determines a predicted load for a subsequent cycle of a switching power converter driving the LED strings based on the programmed current levels and duty cycles. A power conversion controller uses the predicted load information to control switching of the switching power converter. This improves the dynamic response of the switching converter to changing load conditions, thereby improving overall power efficiency and performance of the system.
    Type: Application
    Filed: December 28, 2011
    Publication date: July 4, 2013
    Applicant: IWATT INC,
    Inventors: John William Kesterson, Xiaoyan Wang, Xuecheng Jin, Enzhu Liang, Selcuk Sen
  • Publication number: 20130147374
    Abstract: An LED driver controls current through an LED string. The LED driver generates a boosted PWM signal to drive a PWM transistor in the LED current path such that the PWM transistor maintains a substantially constant VGS, thus minimizing turn-on impedance of the PWM transistor. A current mirror circuit controls peak LED current when the PWM transistor is on. A trimming circuit includes a set of programmable switches to couple or decouple trimming transistor from the LED current path, and allowing for fine calibration of the LED current. By maintaining a low resistance and compensating for current mismatch in the LED current path, the LED driver provides efficient power performance and robustness that is particularly beneficial in high current applications.
    Type: Application
    Filed: December 7, 2011
    Publication date: June 13, 2013
    Applicant: IWATT INC.
    Inventors: Minjong Kim, Enzhu Liang, Xuecheng Jin
  • Publication number: 20130127344
    Abstract: An adaptive switch mode LED driver provides an intelligent approach to driving multiple strings of LEDs. The LED driver determines an optimal current level for each LED channel from a limited set of allowed currents. The LDO driver then determines a PWM duty cycle for driving the LEDs in each LED channel to provide precise brightness control over the LED channels. Beneficially, the LED driver minimizes the power dissipation in the LDO circuits driving each LED string, while also ensuring that the currents in each LED string are maintained within a limited range. A sample and hold LDO allows PWM control over extreme duty cycles with very fast dynamic response. Furthermore, fault protection circuitry ensures fault-free startup and operation of the LED driver.
    Type: Application
    Filed: November 13, 2012
    Publication date: May 23, 2013
    Inventors: Xuecheng Jin, Yu Chong Chang, Yang Li, Maofeng Lan, John W. Kesterson, Xiaoyan Wang, Chenghung Pan
  • Patent number: 8334662
    Abstract: An adaptive switch mode LED driver provides an intelligent approach to driving multiple strings of LEDs. The LED driver determines an optimal current level for each LED channel from a limited set of allowed currents. The LDO driver then determines a PWM duty cycle for driving the LEDs in each LED channel to provide precise brightness control over the LED channels. Beneficially, the LED driver minimizes the power dissipation in the LDO circuits driving each LED string, while also ensuring that the currents in each LED string are maintained within a limited range. A sample and hold LDO allows PWM control over extreme duty cycles with very fast dynamic response. Furthermore, fault protection circuitry ensures fault-free startup and operation of the LED driver.
    Type: Grant
    Filed: September 11, 2009
    Date of Patent: December 18, 2012
    Assignee: iWatt Inc.
    Inventors: Xuecheng Jin, Yu Cheng Chang, Yang Li, Maofeng Lan, John W. Kesterson, Xiaoyan Wang, Chenghung Pan
  • Publication number: 20120223648
    Abstract: A system that provides an intelligent approach to driving multiple strings of LEDs. A processing device determines an optimal current level for each LED string from a limited set of allowed currents. The processing device also determines a PWM duty cycle for driving the LEDs in each LED string to provide precise brightness control over the LED string. The settings for the current level and duty cycle are transmitted to an LED driver for regulating the current and on-off times of the LED strings. Beneficially, the system reduces the size of the LED driver while leveraging existing resources available in the processing device to operate the LEDs in a power efficient manner.
    Type: Application
    Filed: March 3, 2011
    Publication date: September 6, 2012
    Applicant: IWATT INC.
    Inventors: Xuecheng Jin, Minjong Kim, Enzhu Liang, John William Kesterson, Xiaoyan Wang
  • Patent number: 8184762
    Abstract: A digital phase lock loop circuit provides an output with reduced jitter. The digital phase lock loop circuit includes a phase frequency detector that determines a phase difference between a feedback signal and a reference frequency signal to generate an error signal indicative of the phase difference. A numerically controlled oscillator generates a first oscillator output signal with a frequency proportional to the error signal and a second oscillator output signal indicative of jitter of the first oscillator output signal in reference to the reference frequency signal. A phase accuracy extender determines a delay amount from the second oscillator output signal and delays the first oscillator output signal by the delay amount to generate a phase-enhanced output signal with edges aligned with one of a plurality of reference clock signals.
    Type: Grant
    Filed: November 6, 2008
    Date of Patent: May 22, 2012
    Assignee: iWatt, Inc.
    Inventors: John W. Kesterson, Carrie Seim, Selcuk Sen, Xuecheng Jin