Patents by Inventor Der-Jiunn Wang

Der-Jiunn Wang 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).

  • Publication number: 20180315391
    Abstract: A Gamma curve correction method for an LCD sets a ground potential of the LCD as a common voltage and adjusts at least one of a plurality of positive Gamma voltages and a plurality of negative Gamma voltages of the LCD such that the central voltage value of a Gamma curve established by the positive Gamma voltages and the negative Gamma voltages becomes closer to the common voltage. As a result, flickers existing in the images of the LCD are improved.
    Type: Application
    Filed: July 5, 2018
    Publication date: November 1, 2018
    Inventors: Der-Jiunn WANG, Chung-Hsien TSO, Chun-I LIN, Hsing-Shen HUANG
  • Patent number: 10043471
    Abstract: A Gamma curve correction method for an LCD sets a ground potential of the LCD as a common voltage, and adjusts at least one of a plurality of positive Gamma voltages and a plurality of negative Gamma voltages of the LCD such that the central value of a Gamma curve established by the positive Gamma voltages and the negative Gamma voltages becomes closer to the common voltage. As a result, flickers existing in the images of the LCD are improved.
    Type: Grant
    Filed: November 30, 2015
    Date of Patent: August 7, 2018
    Assignee: Richtek Technology Corporation
    Inventors: Der-Jiunn Wang, Chung-Hsien Tso, Chun-I Lin
  • Publication number: 20160171936
    Abstract: A Gamma curve correction method for an LCD sets a ground potential of the LCD as a common voltage, and adjusts at least one of a plurality of positive Gamma voltages and a plurality of negative Gamma voltages of the LCD such that the central value of a Gamma curve established by the positive Gamma voltages and the negative Gamma voltages becomes closer to the common voltage. As a result, flickers existing in the images of the LCD are improved.
    Type: Application
    Filed: November 30, 2015
    Publication date: June 16, 2016
    Inventors: Der-Jiunn WANG, Chung-Hsien TSO, Chun-I LIN
  • Patent number: 8836614
    Abstract: The present invention provides a display panel control circuit, including: a voltage adjustment unit including a high side switch coupled between an output terminal and a high voltage source, a low side switch coupled between the output terminal and a low voltage source, and a voltage adjustment switch coupled between the output terminal and a switching node; a direction control unit, including a first diode having a cathode coupled to the switching node and an anode coupled to a voltage rising node, and a second diode having an anode coupled the switching node and a cathode coupled to a voltage falling node; a voltage rising resistor coupled between the voltage rising node and a shaping voltage source; and a voltage falling resistor coupled between the voltage falling node and the shaping voltage source.
    Type: Grant
    Filed: February 27, 2013
    Date of Patent: September 16, 2014
    Assignee: Richtek Technology Corporation
    Inventor: Der-Jiunn Wang
  • Publication number: 20140239839
    Abstract: The present invention provides a display panel control circuit, including: a voltage adjustment unit including a high side switch coupled between an output terminal and a high voltage source, a low side switch coupled between the output terminal and a low voltage source, and a voltage adjustment switch coupled between the output terminal and a switching node; a direction control unit, including a first diode having a cathode coupled to the switching node and an anode coupled to a voltage rising node, and a second diode having an anode coupled the switching node and a cathode coupled to a voltage falling node; a voltage rising resistor coupled between the voltage rising node and a shaping voltage source; and a voltage falling resistor coupled between the voltage falling node and the shaping voltage source.
    Type: Application
    Filed: February 27, 2013
    Publication date: August 28, 2014
    Applicant: RICHTEK TECHNOLOGY CORPORATION
    Inventor: Der-Jiunn Wang
  • Publication number: 20140015741
    Abstract: A programmable Gamma circuit of a LCD display device includes a control signal generator for generating multiple control signals; one or more voltage-reducing circuits for generating multiple voltage-reduced signals corresponding to a common voltage feedback signal outputted from a LC array of the LCD display device; and multiple amplifying circuits for respectively amplifying the multiple coupled signals to generate multiple Gamma calibration signals. The multiple voltage-reduced signals are respectively coupled with the multiple control signals to generate multiple coupled signals.
    Type: Application
    Filed: June 24, 2013
    Publication date: January 16, 2014
    Inventors: Der-Jiunn WANG, Tien-Jung WU
  • Patent number: 8466666
    Abstract: A multi-stage voltage regulating circuit and method with automatic temperature compensation comprises a plurality of charge-pumps, a temperature compensator, a comparative unit and a control logic circuit; wherein, the temperature compensator detects the ambient temperature and outputs a reference voltage related to the ambient temperature, the comparative unit compares the voltage of the output power source to the reference voltage output by the temperature compensator and outputs a comparative signal based on the comparison, and the control logic circuit controls the charging/discharging operations of the charge-pumps based on the comparative signal and voltages of input power sources connected to said charge-pumps to automatically regulate the voltage of the output power source.
    Type: Grant
    Filed: April 5, 2011
    Date of Patent: June 18, 2013
    Assignee: Richtek Technology Corp.
    Inventors: Der-Jiunn Wang, Kuo-Chen Tsai
  • Patent number: 8193853
    Abstract: For a charge pump, a control circuit switches two or more input voltages to apply to one or more pumping capacitors under auto-sensing control to modulate a maximum pumping voltage as close as to a demanded output voltage to thereby reduce the difference between the maximum pumping voltage and the output voltage for efficiency and thermal improvement of the charge pump. The maximum pumping voltage is produced by mixing the different input voltages and the charge pump may provide more operation modes.
    Type: Grant
    Filed: June 16, 2010
    Date of Patent: June 5, 2012
    Assignee: Richtek Technology Corp.
    Inventors: Wei-Lun Hsieh, Hung-Sung Chu, Der-Jiunn Wang, Kuo-Chen Tsai, Wei-Hsin Wei
  • Publication number: 20120126770
    Abstract: A multi-stage voltage regulating circuit and method with automatic temperature compensation comprises a plurality of charge-pumps, a temperature compensator, a comparative unit and a control logic circuit; wherein, the temperature compensator detects the ambient temperature and outputs a reference voltage related to the ambient temperature, the comparative unit compares the voltage of the output power source to the reference voltage output by the temperature compensator and outputs a comparative signal based on the comparison, and the control logic circuit controls the charging/discharging operations of the charge-pumps based on the comparative signal and voltages of input power sources connected to said charge-pumps to automatically regulate the voltage of the output power source.
    Type: Application
    Filed: April 5, 2011
    Publication date: May 24, 2012
    Applicant: Richtek Technology Corporation
    Inventors: DER-JIUNN WANG, Kuo-Chen Tsai
  • Publication number: 20100321099
    Abstract: For a charge pump, a control circuit switches two or more input voltages to apply to one or more pumping capacitors under auto-sensing control to modulate a maximum pumping voltage as close as to a demanded output voltage to thereby reduce the difference between the maximum pumping voltage and the output voltage for efficiency and thermal improvement of the charge pump. The maximum pumping voltage is produced by mixing the different input voltages and the charge pump may provide more operation modes.
    Type: Application
    Filed: June 16, 2010
    Publication date: December 23, 2010
    Applicant: RICHTEK TECHNOLOGY CORP.
    Inventors: WEI-LUN HSIEH, HUNG-SUNG CHU, DER-JIUNN WANG, KUO-CHEN TSAI, WEI-HSIN WEI
  • Patent number: 7550932
    Abstract: A control device, which controls a power-converting module that is coupled to a light-emitting component, includes a duration detecting unit and a control signal generator. The duration detecting unit compares the duration of a predetermined logic state of a pulsating input dim control signal with a reference time period. The control signal generator is enabled by the duration detecting unit so as to generate a control signal that enables the power-converting module to generate a drive voltage for driving the light-emitting component when the duration of the predetermined logic state is not longer than the reference time period. The duration detecting unit disables the control signal generator to disable the power-converting module when the duration of the predetermined logic state is longer than the reference time period.
    Type: Grant
    Filed: December 18, 2007
    Date of Patent: June 23, 2009
    Inventors: Nien-Hui Kung, Yiu-I Lin, Der-Jiunn Wang, Chao-Hsuan Chuang, Jien-Sheng Chen, Shui-Mu Lin, Wei-Hsin Wei
  • Publication number: 20080150452
    Abstract: A control device, which controls a power-converting module that is coupled to a light-emitting component, includes a duration detecting unit and a control signal generator. The duration detecting unit compares the duration of a predetermined logic state of a pulsating input dim control signal with a reference time period. The control signal generator is enabled by the duration detecting unit so as to generate a control signal that enables the power-converting module to generate a drive voltage for driving the light-emitting component when the duration of the predetermined logic state is not longer than the reference time period. The duration detecting unit disables the control signal generator to disable the power-converting module when the duration of the predetermined logic state is longer than the reference time period.
    Type: Application
    Filed: December 18, 2007
    Publication date: June 26, 2008
    Inventors: Nien-Hui KUNG, Yiu-I LIN, Der-Jiunn WANG, Chao-Hsuan CHUANG, Jien-Sheng CHEN, Shui-Mu LIN, Wei-Hsin WEI
  • Patent number: 7385422
    Abstract: A voltage generating circuit, which generates tri-state logic output in accordance with high, low or floating of the input node, is proposed.
    Type: Grant
    Filed: September 2, 2005
    Date of Patent: June 10, 2008
    Assignee: Richtek Technology Corporation
    Inventors: Shui-Mu Lin, Chien-Sheng Chen, Nien-Hui Kung, Der-Jiunn Wang, Jing-Meng Liu, Wei-Hsin Wei
  • Patent number: 7332879
    Abstract: A control device, which controls a power-converting module that is coupled to a light-emitting component, includes a duration detecting unit and a control signal generator. The duration detecting unit compares the duration of a predetermined logic state of a pulsating input dim control signal with a reference time period. The control signal generator is enabled by the duration detecting unit so as to generate a control signal that enables the power-converting module to generate a drive voltage for driving the light-emitting component when the duration of the predetermined logic state is not longer than the reference time period. The duration detecting unit disables the control signal generator to disable the power-converting module when the duration of the predetermined logic state is longer than the reference time period.
    Type: Grant
    Filed: August 16, 2004
    Date of Patent: February 19, 2008
    Assignee: Richtek Technology Corp.
    Inventors: Nien-Hui Kung, Yiu-I Lin, Der-Jiunn Wang, Chao-Hsuan Chuang, Jien-Sheng Chen, Shui-Mu Lin, Wei-Hsin Wei
  • Patent number: 7271802
    Abstract: A backlight power controller chip comprises a control circuit connected to two switches to turn on and off two display panels of a dual panel display handheld apparatus. The controller chip individually switches the two switches to control the backlight sources of the two display panels. The controller chip is available for various types of display panels.
    Type: Grant
    Filed: May 17, 2004
    Date of Patent: September 18, 2007
    Assignee: Richtek Technology Corp.
    Inventors: Der-Jiunn Wang, Jing-Meng Liu, Chao-Hsuan Chuang, Nien-Hui Kung, Wen-Hung Huang
  • Publication number: 20060279331
    Abstract: A voltage generating circuit, which generates tri-state logic output in accordance with high, low or floating of the input node, is proposed.
    Type: Application
    Filed: September 2, 2005
    Publication date: December 14, 2006
    Inventors: Shui-Mu Lin, Chien-Sheng Chen, Nien-Hui Kung, Der-Jiunn Wang, Jing-Meng Liu, Wei-Hsin Wei
  • Patent number: 7026800
    Abstract: In a method for a DC-DC power conversion performed by a switching mode buck voltage converter, the power conversion is split into two or more stages, and a feed-forward signal is generated by one of the stages and sent to another stage prior thereto. The feed-forward signal is generated by responding to a load current transient, such as output voltage drop, ON-duty increment or decrement occurred in the PWM control loop, error amp output swinging, and any other detectable signals in response to load current transient of the voltage converter. As a result, the performance of the DC-DC voltage converter is improved due to the prior stage modulated early in time, and both lower ripple current and peak current in steady state operations and fast response to load current transient conditions could be simultaneously obtained.
    Type: Grant
    Filed: October 14, 2003
    Date of Patent: April 11, 2006
    Assignee: Richtek Technology Corp.
    Inventors: Jing-Meng Liu, Liang-Pin Tai, Der-Jiunn Wang
  • Publication number: 20060055465
    Abstract: A current mirror circuit that comprises a current mirror unit, a feedback unit and an amplifier unit is provided to output low voltage. The current mirror unit has a plurality of connecting ends, wherein one end couples to a current source, and the other end couples to a loading device. The feedback unit couples to the current mirror unit and the amplifier unit. The amplifier unit couples to the current mirror unit to lockup the voltages of the three notes configured in a plurality of MOS transistors of the current mirror unit. By way of the configuration of the present invention, the current mirror unit can detect an accurate current or map out accurately a push controlling current through the electrical characteristic of the amplifier unit and the feedback of the feedback unit.
    Type: Application
    Filed: September 15, 2004
    Publication date: March 16, 2006
    Inventors: Shui-Mu Lin, Chao-Hsuan Chuang, Nien-Hui Kung, Yiu-I Lin, Der-Jiunn Wang, Jien-Sheng Chen, Wei-Hsin Wei
  • Publication number: 20060033484
    Abstract: A control device, which controls a power-converting module that is coupled to a light-emitting component, includes a duration detecting unit and a control signal generator. The duration detecting unit compares the duration of a predetermined logic state of a pulsating input dim control signal with a reference time period. The control signal generator is enabled by the duration detecting unit so as to generate a control signal that enables the power-converting module to generate a drive voltage for driving the light-emitting component when the duration of the predetermined logic state is not longer than the reference time period. The duration detecting unit disables the control signal generator to disable the power-converting module when the duration of the predetermined logic state is longer than the reference time period.
    Type: Application
    Filed: August 16, 2004
    Publication date: February 16, 2006
    Inventors: Nien-Hui Kung, Yiu-I Lin, Der-Jiunn Wang, Chao-Hsuan Chuang, Jien-Sheng Chen, Shui-Mu Lin, Wei-Hsin Wei
  • Publication number: 20050162361
    Abstract: A frame-shifted technique is disclosed for a dynamic gamma correction method and system that comprises counting the gray levels of each frame to figure out the probability distribution of gray levels in the current frame, and determining the gamma reference voltages according to the probability distribution of gray levels of the current frame for the gamma correction of the next frame.
    Type: Application
    Filed: January 24, 2005
    Publication date: July 28, 2005
    Inventors: Chao-Hsuan Chuang, Yiu-I Lin, Nien-Hui Kung, Der-Jiunn Wang, Jing-Meng Liu