Lapis Semiconductor Co., Ltd.

Lapis Technology Co., Ltd.

Nikon Corporation

Hiroaki Ishii

Masanori Hasuda

Kenji Tonegawa

Shinichi Fukuzako

Tilt monitor and brackets for a digital camera

Tilt monitor for a digital camera

A display device includes a display panel, a gate driver; a source driver, supplying gradation voltage signals to multiple pixel parts via multiple data lines based on a video data signal, and supplying to the gate driver a gate control signal; and a video data transmission part, transmitting the video data signal to the source driver by using LVDS. The video data transmission part assigns, to an empty region that is a region other than regions assigned to multiple pixel data pieces forming one pixel of the video data signal in each data packet defined for a time of transmitting the video data signal for one pixel by using LVDS, an arithmetic value calculated based on the pixel data pieces, and transmits to the source driver together with the pixel data pieces as the video data signal.

Display device and source driver

A source driver includes an output buffer. The output buffer includes: an amplifying unit; a first current control unit that includes a first constant current source and a second constant current source; and a second current control unit that includes a third constant current source and a fourth constant current source. The first constant current source is disposed on a first supply line. The second constant current source is disposed on a second supply line. The third constant current source is connected in parallel to the first supply line, supplies the first power supply voltage to the amplifying unit, and allows turning on and off the supply. The fourth constant current source is connected in parallel to the second supply line, supplies the second power supply voltage to the amplifying unit, and allows turning on and off the supply.

A display driver includes: a conversion part which converts first to n-th display data pieces representing a brightness level of each pixel based on an image signal into first to n-th gradation voltages each having a voltage value corresponding to the brightness level and outputs them, where n is an integer of 2 or more; a polarity inversion signal generation circuit which generates a polarity inversion signal for prompting polarity inversion for each frame display period according to the image signal; a first external terminal which receives an operation mode signal representing a test mode or a normal mode; and a first selector which receives a test polarity inversion signal and the polarity inversion signal, selects and outputs the polarity inversion signal when the operation mode signal represents the normal mode, and selects and outputs the test polarity inversion signal when the operation mode signal represents the test mode.

Display driver and display device using independent test polarity inversion signal

A display device includes a display controller and a plurality of source drivers that supply gradation voltage signals to a plurality of pixel parts in a display panel. The plurality of source drivers each includes a setting register that stores setting data, at least one calculation circuit that performs calculation based on the setting data and calculates a setting value for a gradation voltage signal to be outputted, a source output unit that outputs a gradation voltage signal based on a video data signal and the setting value, and a code value calculation unit that calculates an error detection code value based on the calculation result of the calculation circuit. The display controller detects failure that has occurred in the calculation circuit in the plurality of source drivers, based on a calculation result of the code value in each of the plurality of source drivers.

A source driver is provided, including a first data receiving part that receives a serial data signal via the first transmission line, a selector that outputs a serial data signal from either the first transmission line or the second transmission line according to a switching signal, a second data receiving part that receives the serial data signal output from the selector, a first serial-parallel conversion circuit that serial-parallel converts the serial data signal received by the first data receiving part and outputs the converted signal as first parallel data, a second serial-parallel conversion circuit that serial-parallel converts the serial data signal received by the second data receiving part and outputs the converted signal as second parallel data, and a comparison circuit that compares the first parallel data with the second parallel data and outputs a comparison result when the selector outputs the serial data signal from the first transmission line.

Source driver for display device detecting abnormality in data receiving

Provided is a display panel, a source driver that generates a gradation voltage signal based on an image data signal, a timing controller that supplies the image data signal to the source driver, and an illumination drive unit that controls an amount of light of a backlight that illuminates each of a plurality of areas formed by dividing a display screen in the display panel. The source driver or the timing controller calculates feature values of the image data signal corresponding to each of the plurality of areas of the display panel and supplies a dimming data signal representing the amount of light of the backlight according to the feature values of each area to the illumination drive unit. The illumination drive unit controls the amount of light of the backlight for each of the plurality of areas based on the dimming data signal.

Display device and source driver with local dimming

A display device includes a display panel, a display controller configured to output a video data signal, a gate driver, and a plurality of source drivers which are arranged in an extension direction of gate lines and generate a gradation voltage signal to be supplied to each of a plurality of pixel units based on the video data signal supplied from the display controller. Each of the plurality of source drivers includes a data processing unit configured to share an abnormal state sharing signal indicating whether an abnormality has occurred in communication with the display controller with other source drivers, and when the abnormal state sharing signal indicates that an abnormality has occurred in communication with the display controller, supply a gradation voltage signal corresponding to predetermined gradation data different from a gradation voltage signal based on the video data signal to each of the plurality of pixel units.

A display driver according to the present invention includes a control part and a fault detection circuit. The control part sequentially incorporates first fault detection data and second fault detection data into a video signal during non-display periods of the video signal. The fault detection circuit binarizes each of a first pixel driving voltage and a second pixel driving voltage with a predetermined threshold voltage to obtain a first signal and a second signal. The first pixel driving voltage is generated based on the first fault detection data. The second pixel driving voltage is generated based on the second fault detection data. The fault detection circuit determines whether the first signal and the second signal match and outputs a fault detection signal that indicates a presence of a fault when the first signal and the second signal match.

Display driver, display device, and semiconductor device to detect fault in fixed driving voltage applied to a display panel

First to N-th latches capture N pieces of pixel data indicative of the luminance levels of respective pixels in synchronization with first to N-th capture clock signals each having different edge timing. Voltages corresponding to the pieces of pixel data output from the first to N-th latches are applied to each of the data lines of the display device. In this case, first to N-th flip-flops formed in an N-stage shift register capture a single pulse load signal which is synchronized with a horizontal synchronizing signal in a video signal while sequentially shifting the load signal to subsequent stages in synchronization with a reference timing signal supplied from the outside. Outputs of the first to N-th flip-flops in the N-stage shift register are supplied as first to N-th capture clock signals, to the first to N-th latches, respectively.

Display driver

A display device driver that can display images while preventing noise and suppressing display unevenness is provided. When pixel drive voltages corresponding to the luminance levels of respective pixels indicated by a video signal are applied to the data lines of the display device, the pixel drive voltages are applied to data lines that intersect the scanning lines of the display device at positions where the delay time is larger, at timing later than timing of applying the pixel drive voltages to the data lines that intersect the scanning lines at positions where the delay time is smaller, the delay time being a period of time between start of application of the scanning pulse by the scanning driver and actual arrival of the scanning pulse.

Growing community of inventors

Yokohama, Japan

Hiroaki Ishii