Nec Electronics Corporation

Renesas Electronics Corporation

Masayuki Kumeta

Yoshiharu Hashimoto

Kouji Matsuura

Masayuki Yamaguchi

Takayuki Shu

Akimitsu Tajima

Makoto Sunohara

Masaki Izumikawa

An amplifier circuit includes an operational amplifier having first and second input nodes and one output node which is connected to a data line for which a pixel is provided; a feedback circuit having first and second elements which are connected to one of the first and second input nodes at their one ends; and a first switch section. The first switch section switches an operation mode between a first drive mode in which the other end of the first element is connected to the output node and a second drive mode in which the other end of the second element is connected to the output node.

Drive circuit containing amplifier circuit

A method is provided for driving a liquid crystal display panel including first and second data line sets each including an even number of arrayed data lines, and a plurality of pixels sharing a common electrode having a constant potential. The method is composed of: time-divisionally selecting data lines from each of the first and second data line sets; and providing data signals on the selected data lines to write the data signals into the pixels therethrough. An order of selecting the data lines from each of the first and second data lines and polarities of the data signals written into the pixels are determined so that polarities of the data signals on the data lines selected from the first data line set are opposite to those of the data lines selected from the second data line set.

Apparatus and method for LCD panel drive for achieving time-divisional driving and inversion driving

A display panel driver is composed of a grayscale voltage generator configured to develop a set of different grayscale voltages corresponding to grayscale levels of pixels within a display panel; and a plurality of grayscale selector driver circuits each of which is responsive to pixel data to select one of the grayscale voltages, and to provide a drive voltage corresponding to the selected one of the grayscale voltages for a selected pixel within the display panel. The grayscale voltage generator is allowed to output the set of grayscale voltages during a first period within a horizontal period, and prohibited from outputting the set of grayscale voltages during a second period within the horizontal period.

Apparatus and method for driving display panels for reducing power consumption of grayscale voltage generator

A method of operating a liquid crystal display device includes: (A) time-divisionally driving pixels in a certain line of an LCD panel so that pixels adjacent in a horizontal direction are driven with data signals of opposite polarities. The (A) step includes: (A1) generating a first data signal of a first polarity on a first output terminal of a driver, and then driving a first pixel out of said pixels in the certain line through electrically connecting the first output terminal to the first pixel; and (A2) generating a second data signal of the first polarity on the first output terminal and then driving a second pixel out of said pixels in the certain line through electrically connecting the first output terminal to the second pixel, in succession to the drive of the first pixel.

LCD panel drive adopting time-division and inversion drive

A liquid crystal display apparatus is composed of an LCD panel including data lines, and an LCD driver. The LCD driver includes: a positive drive circuit providing a positive data signal having positive polarity with respect to a ground level of the LCD driver for one of the data lines; and a negative drive circuit providing a negative data signal having negative polarity with respect to the ground level of the LCD driver for another one of the data lines.

Liquid crystal display for implmenting improved inversion driving technique

A display device is provided with a display controller, a source driver, and a liquid crystal panel, and two pairs of wirings are provided between the display controller and the source driver. The display controller is provided with a V-I conversion circuit for image data and a mode register, and the source driver is provided with an I-V conversion circuit for image data. The V-I conversion circuit for image data connects either one of a pair of the wirings to an earth electrode and sets the other one to a floating state based on the image data. The I-V conversion circuit for image data allows electric current to flow in the wiring out of a pair of the wirings, which is connected to the earth electrode, and converts the image data into a pair of complementary current signals to receive them. Further, the I-V conversion circuit for image data stops the current signal by a control signal from the mode register when the image data is not transmitted.

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Kanagawa, Japan

Masayuki Kumeta