Patents by Inventor Yoshikazu Yokota

Yoshikazu Yokota 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: 20090085857
    Abstract: The present invention provides a liquid crystal display controller device and method which provides for a full and/or partial display with good display quality and/or low power consumption based on the scanning period for an active scan line being dependent upon a number of reference clock pulses. Some embodiments of the present invention include one or more of the following features: keeping the frequency substantially constant for different numbers of active scan lines, allowing change of the frequency due to characteristics of the LCD, displaying gradation with near linear effective voltage characteristics, displaying graduation data with lower power, or displaying a partial or full screen in a mobile device, for example, a cell phone.
    Type: Application
    Filed: October 13, 2008
    Publication date: April 2, 2009
    Applicant: Renesas Technology Corporation
    Inventors: Yasuyuki Kudo, Tsutomu Furuhashi, Yoshikazu Yokota, Toshimitsu Matsudo, Atsuhiro Higa
  • Patent number: 7480164
    Abstract: There is to be provided a liquid crystal drive controller with a built-in power supply circuit wherein latch-up is made difficult to arise even if one amplitude level of the segment line drive voltage is set to the ground potential and the levels of other liquid crystal drive voltages are determined accordingly. A semiconductor integrated circuit with a built-in power supply circuit, wherein a negative voltage generated in a power supply circuit is applied to a substrate or a well region as a bias voltage, is provided with a switch for temporarily applying the ground potential to the substrate or well region to be biased with the negative voltage at the time of starting up the power supply circuit.
    Type: Grant
    Filed: October 15, 2007
    Date of Patent: January 20, 2009
    Assignee: Renesas Technology Corp.
    Inventors: Kazuya Endo, Naoki Miyamoto, Toshio Mizuno, Takayuki Nakaji, Takatoshi Uchida, Kazuo Ookado, Yoshikazu Yokota
  • Patent number: 7453433
    Abstract: The present invention provides a liquid crystal display controller device and method which provides for a full and/or partial display with good display quality and/or low power consumption based on the scanning period for an active scan line being dependent upon a number of reference clock pulses. Some embodiments of the present invention include one or more of the following features: keeping the frequency substantially constant for different numbers of active scan lines, allowing change of the frequency due to characteristics of the LCD, displaying gradation with near linear effective voltage characteristics, displaying graduation data with lower power, or displaying a partial or full screen in a mobile device, for example, a cell phone.
    Type: Grant
    Filed: June 29, 2005
    Date of Patent: November 18, 2008
    Assignee: Renesas Technology Corp.
    Inventors: Yasuyuki Kudo, Tsutomu Furuhashi, Yoshikazu Yokota, Toshimitsu Matsudo, Atsuhiro Higa
  • Patent number: 7355596
    Abstract: A matrix type liquid crystal display device has a function of suppressing power consumption without calling for an extra circuit arrangement such as the arrangement of storage capacitance and wiring to storage capacitance and without disposing new external components. A switch is disposed in the liquid crystal display device to temporarily short-circuit both column electrodes and common electrodes sandwiching a liquid crystal between them in synchronism with an alternation timing.
    Type: Grant
    Filed: August 9, 2004
    Date of Patent: April 8, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Yasuyuki Kudo, Yoshikazu Yokota, Kazunari Kurokawa, Atsushiro Higa
  • Publication number: 20080049480
    Abstract: There is to be provided a liquid crystal drive controller with a built-in power supply circuit wherein latch-up is made difficult to arise even if one amplitude level of the segment line drive voltage is set to the ground potential and the levels of other liquid crystal drive voltages are determined accordingly. A semiconductor integrated circuit with a built-in power supply circuit, wherein a negative voltage generated in a power supply circuit is applied to a substrate or a well region as a bias voltage, is provided with a switch for temporarily applying the ground potential to the substrate or well region to be biased with the negative voltage at the time of starting up the power supply circuit.
    Type: Application
    Filed: October 15, 2007
    Publication date: February 28, 2008
    Inventors: Kazuya Endo, Naoki Miyamoto, Toshio Mizuno, Takayuki Nakaji, Takatoshi Uchida, Kazuo Ookado, Yoshikazu Yokota
  • Patent number: 7317627
    Abstract: There is to be provided a liquid crystal drive controller with a built-in power supply circuit wherein latch-up is made difficult to arise even if one amplitude level of the segment line drive voltage is set to the ground potential and the levels of other liquid crystal drive voltages are determined accordingly. A semiconductor integrated circuit with a built-in power supply circuit, wherein a negative voltage generated in a power supply circuit is applied to a substrate or a well region as a bias voltage, is provided with a switch for temporarily applying the ground potential to the substrate or well region to be biased with the negative voltage at the time of starting up the power supply circuit.
    Type: Grant
    Filed: May 8, 2007
    Date of Patent: January 8, 2008
    Assignee: Renesas Technology Corp.
    Inventors: Kazuya Endo, Naoki Miyamoto, Toshio Mizuno, Takayuki Nakaji, Takatoshi Uchida, Kazuo Ookado, Yoshikazu Yokota
  • Patent number: 7286110
    Abstract: In conventional liquid crystal display controllers such as for portable telephone sets, the display is reduced in the stand-by state but the liquid crystal display duty is not changed, i.e., even the common electrodes of the rows that are not producing display are scanned, and the consumption of electric power is not decreased to a sufficient degree in the stand-by state. A liquid crystal display controller (2) includes a drive duty selection register (34) capable of being rewritten by a microprocessor (1), and a drive bias selection register (32). When the display is changed from the whole display on a liquid crystal display panel (3) to a partial display on part of the rows only, the preset values of the drive duty selection register and of the drive bias selection register are changed, so that the display is selectively produced on a portion of the liquid crystal display panel at a low voltage with a low-duty drive.
    Type: Grant
    Filed: February 17, 2004
    Date of Patent: October 23, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Yoshikazu Yokota, Kunihiko Tani, Gorou Sakamaki, Katsuhiko Yamamoto, Takashi Yoneoka, Kazuhisa Higuchi, Kimihiko Sugiyama
  • Publication number: 20070211508
    Abstract: There is to be provided a liquid crystal drive controller with a built-in power supply circuit wherein latch-up is made difficult to arise even if one amplitude level of the segment line drive voltage is set to the ground potential and the levels of other liquid crystal drive voltages are determined accordingly. A semiconductor integrated circuit with a built-in power supply circuit, wherein a negative voltage generated in a power supply circuit is applied to a substrate or a well region as a bias voltage, is provided with a switch for temporarily applying the ground potential to the substrate or well region to be biased with the negative voltage at the time of starting up the power supply circuit.
    Type: Application
    Filed: May 8, 2007
    Publication date: September 13, 2007
    Inventors: Kazuya Endo, Naoki Miyamoto, Toshio Mizuno, Takayuki Nakaji, Takatoshi Uchida, Kazuo Ookado, Yoshikazu Yokota
  • Patent number: 7233511
    Abstract: There is to be provided a liquid crystal drive controller with a built-in power supply circuit wherein latch-up is made difficult to arise even if one amplitude level of the segment line drive voltage is set to the ground potential and the levels of other liquid crystal drive voltages are determined accordingly. A semiconductor integrated circuit with a built-in power supply circuit, wherein a negative voltage generated in a power supply circuit is applied to a substrate or a well region as a bias voltage, is provided with a switch for temporarily applying the ground potential to the substrate or well region to be biased with the negative voltage at the time of starting up the power supply circuit.
    Type: Grant
    Filed: August 14, 2006
    Date of Patent: June 19, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Kazuya Endo, Naoki Miyamoto, Toshio Mizuno, Takayuki Nakaji, Takatoshi Uchida, Kazuo Ookado, Yoshikazu Yokota
  • Publication number: 20070085793
    Abstract: A display device for displaying display data includes a display panel having pixel sections in a matrix form, a scanning circuit which selects a line of the pixel sections, a generation circuit which generates a plurality of gray-scale voltages based on a reference voltage, and a selection circuit which selects a gray-scale voltage corresponding to the display data from the plurality of gray-scale voltages, and outputs the gray-scale voltage thus selected to a pixel section of the display panel. The generation circuit one of increases and decreases a steady-state current of the generation circuit at a second period within one scanning period of the scanning circuit.
    Type: Application
    Filed: December 12, 2006
    Publication date: April 19, 2007
    Inventors: Yasuyuki Kudo, Atsuhiro Higa, Yoshikazu Yokota, Hiroshi Kurihara, Kazunari Kurokawa
  • Publication number: 20070052654
    Abstract: In conventional liquid crystal display controllers such as for portable telephone sets, the display is reduced in the stand-by state but the liquid crystal display duty is not changed, i.e., even the common electrodes of the rows that are not producing display are scanned, and the consumption of electric power is not decreased to a sufficient degree in the stand-by state. A liquid crystal display controller (2) includes a drive duty selection register (34) capable of being rewritten by a microprocessor (1), and a drive bias selection register (32). When the display is changed from the whole display on a liquid crystal display panel (3) to a partial display on part of the rows only, the preset values of the drive duty selection register and of the drive bias selection register are changed, so that the display is selectively produced on a portion of the liquid crystal display panel at a low voltage with a low-duty drive.
    Type: Application
    Filed: November 8, 2006
    Publication date: March 8, 2007
    Inventors: Yoshikazu Yokota, Kunihiko Tani, Gorou Sakamaki, Katsuhiko Yamamoto, Takashi Yoneoka, Kazuhisa Higuchi, Kimihiko Sugiyama
  • Publication number: 20070035503
    Abstract: There is provided a display driver control circuit which is just suitable for display drive including display with a small amount of change and display with a large amount of change and can realize saving of chip area and reduction of power consumption and cost. In this display driver control circuit, memory capacity of an internal display memory is set smaller than amount of data of one display picture of a display panel as the drive object, and the display data can be transferred with the system in which externally inputted display data is once stored in the display memory and is then sent of a drive circuit to output a drive signal and with the system in which the display data is sent in direct to the drive circuit by way of no display memory to output a drive signal. Moreover, both transfer methods can be executed on the time division basis.
    Type: Application
    Filed: October 24, 2006
    Publication date: February 15, 2007
    Inventors: Yasuhito Kurokawa, Shigeru Ohta, Kunihiko Tani, Goro Sakamaki, Yoshikazu Yokota
  • Patent number: 7151549
    Abstract: A display device or a display driving device includes a display memory for storing display data; a histogram memory for storing frequencies of gray-scale voltages every line; a gray-scale voltage generation circuit for generating a plurality of gray-scale voltages on the basis of reference voltages, a current quantity of a circuit for generating each of the plurality of gray-scale voltages being changed according to a frequency of the gray-scale voltage; and a voltage selector section for selecting a gray-scale voltage to be applied to each of the plurality of pixel sections, from the plurality of gray-scale voltages.
    Type: Grant
    Filed: April 14, 2004
    Date of Patent: December 19, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Yasuyuki Kudo, Atsuhiro Higa, Yoshikazu Yokota, Hiroshi Kurihara, Kazunari Kurokawa
  • Publication number: 20060274015
    Abstract: There is to be provided a liquid crystal drive controller with a built-in power supply circuit wherein latch-up is made difficult to arise even if one amplitude level of the segment line drive voltage is set to the ground potential and the levels of other liquid crystal drive voltages are determined accordingly. A semiconductor integrated circuit with a built-in power supply circuit, wherein a negative voltage generated in a power supply circuit is applied to a substrate or a well region as a bias voltage, is provided with a switch for temporarily applying the ground potential to the substrate or well region to be biased with the negative voltage at the time of starting up the power supply circuit.
    Type: Application
    Filed: August 14, 2006
    Publication date: December 7, 2006
    Inventors: Kazuya Endo, Naoki Miyamoto, Toshio Mizuno, Takayuki Nakaji, Takatoshi Uchida, Kazuo Ookado, Yoshikazu Yokota
  • Patent number: 7145541
    Abstract: There is provided a display driver control circuit which is just suitable for display drive including display with a small amount of change and display with a large amount of change and can realize saving of chip area and reduction of power consumption and cost. In this display driver control circuit, memory capacity of an internal display memory is set smaller than amount of data of one display picture of a display panel as the drive object, and the display data can be transferred with the system in which externally inputted display data is once stored in the display memory and is then sent of a drive circuit to output a drive signal and with the system in which the display data is sent in direct to the drive circuit by way of no display memory to output a drive signal. Moreover, both transfer methods can be executed on the time division basis.
    Type: Grant
    Filed: February 26, 2003
    Date of Patent: December 5, 2006
    Assignee: Renesas Technology Corp.
    Inventors: Yasuhito Kurokawa, Shigeru Ohta, Kunihiko Tani, Goro Sakamaki, Yoshikazu Yokota
  • Patent number: 7110274
    Abstract: There is to be provided a liquid crystal drive controller with a built-in power supply circuit wherein latch-up is made difficult to arise even if one amplitude level of the segment line drive voltage is set to the ground potential and the levels of other liquid crystal drive voltages are determined accordingly. A semiconductor integrated circuit with a built-in power supply circuit, wherein a negative voltage generated in a power supply circuit is applied to a substrate or a well region as a bias voltage, is provided with a switch for temporarily applying the ground potential to the substrate or well region to be biased with the negative voltage at the time of starting up the power supply circuit.
    Type: Grant
    Filed: January 12, 2005
    Date of Patent: September 19, 2006
    Assignee: Renesas Technology Corp.
    Inventors: Kazuya Endo, Naoki Miyamoto, Toshio Mizuno, Takayuki Nakaji, Takatoshi Uchida, Kazuo Ookado, Yoshikazu Yokota
  • Patent number: 7068253
    Abstract: The present invention provides a liquid crystal display controller device and method which provides for a full and/or partial display with good display quality and/or low power consumption based on the scanning period for an active scan line being dependent upon a number of reference clock pulses. Some embodiments of the present invention include one or more of the following features: keeping the frequency substantially constant for different numbers of active scan lines, allowing change of the frequency due to characteristics of the LCD, displaying gradation with near linear effective voltage characteristics, displaying graduation data with lower power, or displaying a partial or full screen in a mobile device, for example, a cell phone.
    Type: Grant
    Filed: June 25, 2001
    Date of Patent: June 27, 2006
    Assignee: Renesas Technology Corporation
    Inventors: Yasuyuki Kudo, Tsutomu Furuhashi, Yoshikazu Yokota, Toshimitsu Matsudo, Atsuhiro Higa
  • Publication number: 20050280623
    Abstract: A display control device and technique for controlling displays on a display unit, in which a plurality of display segments are two-dimensionally arranged (e.g. a dot matrix type display unit), is provided. The technique is effectively applicable to a write data latch circuit of a memory for storing display data in the display control device, such as, for example, a liquid crystal display control device, a mobile electronic apparatus, etc. A display drive control technique for controlling a moving picture display mode of a display device is also provided. The display drive control circuit controls a picture display mode of a display device for displaying still pictures and moving pictures to a liquid crystal display device, such as, for example, a dot matrix type display devices, an organic EL display device, etc.
    Type: Application
    Filed: January 7, 2005
    Publication date: December 22, 2005
    Inventors: Kunihiko Tani, Yoshikazu Yokota, Goro Sakamaki, Takashi Ohyama, Shigeru Ohta, Kei Tanabe
  • Publication number: 20050243051
    Abstract: The present invention provides a liquid crystal display controller device and method which provides for a full and/or partial display with good display quality and/or low power consumption based on the scanning period for an active scan line being dependent upon a number of reference clock pulses. Some embodiments of the present invention include one or more of the following features: keeping the frequency substantially constant for different numbers of active scan lines, allowing change of the frequency due to characteristics of the LCD, displaying gradation with near linear effective voltage characteristics, displaying graduation data with lower power, or displaying a partial or full screen in a mobile device, for example, a cell phone.
    Type: Application
    Filed: June 29, 2005
    Publication date: November 3, 2005
    Applicant: Hitachi, Ltd.
    Inventors: Yasuyuki Kudo, Tsutomu Furuhashi, Yoshikazu Yokota, Toshimitsu Matsudo, Atsuhiro Higa
  • Publication number: 20050174522
    Abstract: A liquid crystal display device comprises a liquid crystal display panel and a semiconductor integrated circuit for driving and controlling the liquid crystal display panel. The number of input/output wires connected to I/O terminals (bonding pads) of the semiconductor integrated circuit is reduced so as to simplify wiring patterns of the I/O wires, whereby degrees of freedom in arranging the I/O wiring patterns are enhanced. The panel has a pair of insulating substrate, and the semiconductor integrated circuit is mounted on one of the paired substrates. The semiconductor integrated circuit has a mode terminal which is fixed to a power supply potential or to a reference potential during operation of the integrated circuit, and power supply dummy terminals connected to the power supply potential or reference potential inside the semiconductor integrated circuit. The wiring patterns formed on the paired insulating substrates connect the mode terminal to the power supply dummy terminals.
    Type: Application
    Filed: April 6, 2005
    Publication date: August 11, 2005
    Inventors: Kazuhisa Higuchi, Yoshikazu Yokota, Kimihiko Sugiyama