Patents Assigned to Renesas SP Drivers Inc.
  • Patent number: 9025701
    Abstract: A receiver is composed of a receiver-side amplifier which receives a clock signal, a receiver-side amplifier which receives a data signal, a variable delay circuit which generates a delay-adjusted clock signal and a delay-adjusted data signal by delaying the clock signal and the data signal, a latch circuit section which latches the delay-adjusted data signal in synchronous with the delay-adjusted clock signal, and a skew detecting circuit which generates skew detection data that by latching a specific data sequence transmitted as the data signal in synchronous with a first clock signal to Nth clock signal (N is an integer equal to or more than 2) with different delay times from the clock signal. The delay time in the variable delay circuit is controlled according to the skew detection data.
    Type: Grant
    Filed: February 18, 2014
    Date of Patent: May 5, 2015
    Assignee: Renesas SP Drivers Inc.
    Inventors: Keiichi Itoigawa, Shinichi Ogou, Jun Kurosawa, Takashi Tamura
  • Patent number: 8923636
    Abstract: A circuit includes an image decompression circuit configured to receive compressed image data which are generated by compressing image data of a set of pixels of a target block by using a selected compression method selected from a plurality of compression methods based on a correlation among said image data of said set of pixels of said target block, and to generate decompressed image data by decompressing said compressed image data by using a decompression method corresponding to said selected compression method.
    Type: Grant
    Filed: January 31, 2013
    Date of Patent: December 30, 2014
    Assignee: Renesas SP Drivers Inc.
    Inventors: Hirobumi Furihata, Takashi Nose
  • Publication number: 20140361429
    Abstract: A semiconductor device includes: a semiconductor chip having a main face which has a pair of long sides parallel to each other and a pair of short sides orthogonal to the pair of long sides; first bumps arrayed in a first bump placement region of the semiconductor chip, the first bump placement region being positioned along one of the pair of long sides; second bumps arrayed in a second bump placement region of the semiconductor chip, the second bump placement region being positioned along the other of the pair of long sides; first power lines disposed in a region between the first bump placement region and the second bump placement region, the first power lines extending in a direction parallel to the pair of long sides; and third bumps integrated on the semiconductor chip. Each of the third bumps provides short-circuiting of the first power lines.
    Type: Application
    Filed: May 13, 2014
    Publication date: December 11, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventors: Hisao Nakamura, Yuichi Nakagomi, Shinya Suzuki
  • Patent number: 8907962
    Abstract: No flicker is displayed on the display screen during display of moving pictures and power consumption can be reduced by adding a high quality moving picture display function. Moreover, the number of times of transfer of moving pictures by comprising a still-picture • text • system • I/O bus • interface and a moving picture interface (external display interface), providing a display operation change register (DM) and a RAM access change register (RM) which are changed selectively depending on display content (display mode) displayed on a display device and displaying the display data on the display device via a picture memory even in the moving picture display mode.
    Type: Grant
    Filed: September 10, 2013
    Date of Patent: December 9, 2014
    Assignee: Renesas SP Drivers Inc.
    Inventors: Goro Sakamaki, Takashi Ohyama, Shigeru Ohta, Kei Tanabe
  • Publication number: 20140347297
    Abstract: The semiconductor device includes: a display panel (e.g. a liquid crystal display panel) which has a capacitor for holding an electric charge corresponding to image data in quantity in each pixel and displays image data of each frame made up of lines; and a display-drive circuit for activating the display panel. The display-drive circuit performs a time-division action in which a one-frame period includes display-drive periods in which the display panel is activated, and blank periods in which the activation of the display panel remains stopped, which are arranged alternately. The display-drive circuit drives, for display, lines of one frame which are almost evenly distributed to display-drive periods in groups of several lines.
    Type: Application
    Filed: May 21, 2014
    Publication date: November 27, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventor: Sosuke Tsuji
  • Publication number: 20140333608
    Abstract: There is provided a display driver IC including an image memory which stores display data supplied from a host processor, a timing controller which reads the display data from the image memory and drives a connected display panel, and an internal clock oscillation circuit which supplies an internal clock to the timing controller. An oscillation frequency of the internal clock oscillation circuit is calibrated on the basis of an external clock supplied from an external device. An operation of the host processor which supplies the external clock can be suspended, thereby reducing power consumption of a display apparatus as a whole. Therefore, an expensive oscillation vibrator is not necessary, and thus it is possible to minimize an increase in a cost of the display apparatus.
    Type: Application
    Filed: April 29, 2014
    Publication date: November 13, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventors: Yosuke Okairi, Kota Kitamura
  • Publication number: 20140313115
    Abstract: A liquid crystal display apparatus includes a liquid crystal display panel having gate lines and source lines, a GIP circuit which drives the gate lines and a source driver IC3 which drives the source lines. The source driver IC3 includes a gate control signal generator which generates gate control signals SOUT1-SOUTn which control the GIP circuit. The gate control signal generator is configured so that it is possible to control the waveforms of the gate control signals SOUT1-SOUTn in software.
    Type: Application
    Filed: March 28, 2014
    Publication date: October 23, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventors: Satoshi Saito, Kota Kitamura, Hajime Tanabe
  • Publication number: 20140313183
    Abstract: The display driver includes an image memory which is configured by including a plurality of memory mats, a plurality of power supply switches which can perform an ON and OFF control of power supply to each of the plurality of memory mats, and a control circuit which turns on or off the power supply switches. The control circuit turns on the plurality of power supply switches in such a manner that the power supply to the memory mat to which the image data is written at an initial time, among the plurality of memory mats, becomes stable earlier than the power supply to the other memory mats.
    Type: Application
    Filed: April 5, 2014
    Publication date: October 23, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventors: Masashige Harada, Kunihiko Tani, Sosuke Suji
  • Publication number: 20140313146
    Abstract: The drive circuit operable to output a drive pulse pattern to drive electrodes of a touch panel is arranged so that it can change the pulse frequency of the drive pulse pattern for each drive electrode. The detection circuit operable to detect signal changes arising on detection electrodes of the touch panel for each drive pulse pattern output by the drive circuit is arranged so that it can change the sampling frequency of signal change for each detection electrode. The range to make higher the pulse frequency of the drive pulse pattern for each drive electrode, and the sampling frequency of signal change for each detection electrode is variably controlled according to a touch position where a touch has been detected by use of a detection signal detected by the detection circuit.
    Type: Application
    Filed: April 5, 2014
    Publication date: October 23, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventor: Isao Munechika
  • Publication number: 20140298065
    Abstract: A display device includes a boosting power supply circuit, a logic circuit and a charge transport path. The boosting power supply circuit generates a boosted power supply voltage by boosting an analog power supply voltage. The logic circuit is responsive to a decrease in a voltage level on at least one of power supply lines to which analog and logic power supply voltages are supplied for controlling a source line drive circuitry and a gate line drive circuitry to discharge charges accumulated in the display panel. The charge transport path is configured to transport charges from a power supply line on which the boosted power supply voltage is generated to a power supply line which supplies an internal logic power supply voltage to the logic circuit in response to the decrease in the voltage level on the at least one of the first and second power supply lines.
    Type: Application
    Filed: March 28, 2014
    Publication date: October 2, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventor: Goro Sakamaki
  • Publication number: 20140292688
    Abstract: The driver IC includes: a control circuit operable to perform control for creating the timing of detection by a touch panel in a non-display drive period during which the action of a drive circuit remains stopped, and for creating a display drive period during which the drive circuit drives the display panel, and the non-display drive period; and a data RAM operable to hold display data of more than one display line, but smaller than one display frame in capacity. The control circuit performs control for alternately creating the display and non-display drive periods by repeating a memory-addressing operation for writing display data supplied from outside into the RAM and reading the display data from the RAM at a speed faster than the writing speed to provide the read data to the drive circuit two or more times in a period of one display frame according to a wraparound method.
    Type: Application
    Filed: March 16, 2014
    Publication date: October 2, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventor: Isao Munechika
  • Publication number: 20140267206
    Abstract: For each display line cycle, inputs to a pair of differential input terminals of a driving circuit are alternately switched in a cycle shorter than the display line cycle between a gradation voltage and a reference voltage. According to this, a chopping operation of switching polarities of offset appearing at the output of the driving circuit within one display line is performed for a plurality of times, and accordingly, a pixel of each display line maintains brightness information in which the chopping operation is already performed. As a result, although a frame cycle is lengthened, it is difficult to visually recognize a brightness difference caused by the offset.
    Type: Application
    Filed: March 1, 2014
    Publication date: September 18, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventors: Toshiyuki Takani, Toshikazu Tachibana, Shinobu Notomi, Takesada Akiba
  • Publication number: 20140253536
    Abstract: The driver IC generates a common voltage to be applied to a common electrode of pixels of a display panel, and generates a high level of a pulse voltage used for driving, by pulses, drive electrodes of a touch panel with its low level set at the common voltage based on data held by a memory region for holding voltage-designating data of the common voltage and amplitude-designating data of the pulse voltage. In addition, the driver IC outputs the common voltage to drive terminals in synchronization with the action timing of the display panel, and outputs a pulse voltage having an amplitude of the high level with respect to the common voltage to the drive terminals in synchronization with the action timing of a touch panel.
    Type: Application
    Filed: March 1, 2014
    Publication date: September 11, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventors: Hideaki Honda, Hirofumi Sonoyama, Kazuhiro Okamura
  • Publication number: 20140253423
    Abstract: A display panel driver includes: a grayscale amplifier receiving an input grayscale reference voltage and generating an output grayscale reference voltage corresponding to the input grayscale reference voltage; a voltage dividing resistor receiving the output grayscale reference voltage and generating a plurality of grayscale voltages by using the received output grayscale reference voltage; a decoder circuit selecting grayscale voltages from among the plurality of grayscale voltages in response to image data and outputting the selected grayscale voltages; and an output circuit outputting drive voltages corresponding to the selected grayscale voltages to output terminals to be connected to source lines of a display panel. The grayscale amplifier is configured such that the output grayscale reference voltage is adjustable by adjusting an offset voltage of the grayscale amplifier.
    Type: Application
    Filed: March 7, 2014
    Publication date: September 11, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventor: Takao Kinsho
  • Publication number: 20140253525
    Abstract: One display frame period is divided into one or a plurality of display driving periods and non-display driving periods, and immediately before transition from the non-display driving period to the display driving period, a dummy driving period is inserted. During the dummy driving period, using dummy data changed from display data at the time of driving stop of a signal electrode during the non-display driving period, driving of the signal electrode starts. Thereafter, a display line is selected, and, using the display data corresponding to each display line selected, the signal electrode is driven.
    Type: Application
    Filed: March 1, 2014
    Publication date: September 11, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventor: Isao Munechika
  • Publication number: 20140241465
    Abstract: A receiver is composed of a receiver-side amplifier which receives a clock signal, a receiver-side amplifier which receives a data signal, a variable delay circuit which generates a delay-adjusted clock signal and a delay-adjusted data signal by delaying the clock signal and the data signal, a latch circuit section which latches the delay-adjusted data signal in synchronous with the delay-adjusted clock signal, and a skew detecting circuit which generates skew detection data that by latching a specific data sequence transmitted as the data signal in synchronous with a first clock signal to Nth clock signal (N is an integer equal to or more than 2) with different delay times from the clock signal. The delay time in the variable delay circuit is controlled according to the skew detection data.
    Type: Application
    Filed: February 18, 2014
    Publication date: August 28, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventors: Keiichi Itoigawa, Shinichi Ogou, Jun Kurosawa, Takashi Tamura
  • Publication number: 20140232954
    Abstract: The driver IC used to activate a display panel has a free region which is proactively provided therein so as to separate its external connection terminals from an edge side thereof by a distance representing at least one row of the terminals. In mounting the driver IC on a display panel by COG technique, the driver IC may be COG-mounted so that bent parts of lead-out lines led out from the display panel and bent at a midway along their lengths to have a narrowed pitch are in position to overlie the free region. The same effect as achieved by reducing the size of the short side of the driver IC by the size of the free region can be obtained. According to the invention, the reduction in frame size of an image-display panel can be readily realized without the need for reducing the chip size of a driver IC.
    Type: Application
    Filed: February 4, 2014
    Publication date: August 21, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventor: Shinya Suzuki
  • Publication number: 20140210776
    Abstract: A common touch panel controller is used for performing touch detection by driving both a touch panel superimposed on a display panel of a touch panel display portion for display, and a touch sensor superimposed on a touch key pattern of a touch key input portion for buttons. A control circuit capable of switching detection characteristics of a detection circuit common to the both in accordance with detection from the touch panel display portion and detection from the touch key input portion is adopted in the touch panel controller.
    Type: Application
    Filed: January 4, 2014
    Publication date: July 31, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventors: Tsuyoshi Kuroiwa, Tatsuya Ishii
  • Publication number: 20140210750
    Abstract: The touch panel controller activates a touch panel having a detection plane superposed on a display plane of a display device, and performs a touch detection. The touch panel controller uses a cycle of 1/n (n is a positive integer) of a display frame cycle on the display plane as the detection frame cycle of the detection plane. The touch panel controller decides an order of driving the detection-scan electrodes in each detection frame cycle according to predetermined phase-delay and phase-advance positions with respect to a display-scan electrode drive position of the display device so as to correspond to an order of the detection-scan electrode array of the touch panel. The touch panel controller makes possible to avoid the coincidence of display-scan and touch-detection positions without thinning touch detections even with the detection frame cycle of a touch sensor shorter than the display frame cycle of a liquid crystal panel.
    Type: Application
    Filed: January 29, 2014
    Publication date: July 31, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventors: Yusuke Uchida, Tatsuya Ishii, Tsuyoshi Kuroiwa, Akihito Akai, Hisayoshi Kajiwara, Kazuo Okado
  • Publication number: 20140210751
    Abstract: A semiconductor device including a display driving circuit that drives a display panel, a touch detection signal driving circuit that applies a touch detection signal to a touch sensor, and a touch state detection circuit that receives a signal obtained by observing the touch sensor is configured as follows. A connection switching circuit that switches connection between a terminal and an internal circuit is included therein. The connection switching circuit switches connection with the terminal by selecting one of at least two of the display driving circuit, the touch detection signal driving circuit and the touch state detection circuit. A protection circuit which is capable of changing a protection voltage level is connected to the terminal, and the protection voltage level varies depending on the signal amplitude of the circuit selected by the connection switching circuit.
    Type: Application
    Filed: January 29, 2014
    Publication date: July 31, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventors: Kazuhiro Okamura, Shigeru Ota