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.

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.

Abstract: In a display driver, one scanning period is divided into a period P and a subsequent period D. In the period P, a pre-charge voltage equal to an original data voltage is applied in a time-sharing manner to data lines in one block, and in the period D after the period P, the original data voltage is applied again.

Abstract: The present invention is to provide a semiconductor device that can correctly switch endians on the outside even if the endian of a parallel interface is not recognized on the outside. The semiconductor device includes a switching circuit and a first register. The switching circuit switches between whether a parallel interface with the outside is to be used as a big endian or a little endian. A first register holds control data of the switching circuit. The switching circuit regards the parallel interface as the little endian when first predetermined control information, that is unchanged in the values of specific bit positions even if its high-order and low-order bit positions are transposed, is supplied to the first register, and regards the parallel interface as the big endian when second predetermined control information, that is unchanged in the values of specific bit positions even if its high-order and low-order bit positions are transposed, is supplied to the first register.

Abstract: A YUV format to be stored in a memory is selected from A or B by a format judging unit for RGB data that is the input output display data of a memory unit, based on the comparison between chrominance (U, V) difference information on horizontal two pixels and the threshold values of U difference and V difference to be resistor-set at a format judging unit. The YUV data and information of A or B that are YUV format-converted at the format conversion unit are stored in the memory. The selection of the YUV format of A or B is, when the chrominance difference information is small as compared with the threshold value the format is YUV 422 (B conversion), and when it is large the format is that the low order bits of Y, U, V of each pixel are reduced (A conversion).

Abstract: In a display driver, one scanning period is divided into a period P and a subsequent period D. In the period P, a pre-charge voltage equal to an original data voltage is applied in a time-sharing manner to data lines in one block, and in the period D after the period P, the original data voltage is applied again.

Abstract: The present invention is to provide a semiconductor device that can correctly switch endians on the outside even if the endian of a parallel interface is not recognized on the outside. The semiconductor device includes a switching circuit and a first register. The switching circuit switches between whether a parallel interface with the outside is to be used as a big endian or a little endian. A first register holds control data of the switching circuit. The switching circuit regards the parallel interface as the little endian when first predetermined control information, that is unchanged in the values of specific bit positions even if its high-order and low-order bit positions are transposed, is supplied to the first register, and regards the parallel interface as the big endian when second predetermined control information, that is unchanged in the values of specific bit positions even if its high-order and low-order bit positions are transposed, is supplied to the first register.

Abstract: A semiconductor circuit with the reduced scale of circuitry and a semiconductor integrated circuit chip which is obtained by integrating the semiconductor circuit and enables chip size reduction are provided. For this purpose, a two-decode method is used. The method uses: a pre-decode circuit comprising a first decoder of the preceding stage which decodes an arbitrary bit of an address signal of eight bits and a second decoder of the preceding stage which decodes the remaining bits; level conversion circuits which shift the output of the pre-decode circuit; and post-decode circuits which decode the decode outputs of the decoders in the pre-decode circuit, level-converted through the level conversion circuits.

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.

Abstract: A semiconductor circuit with the reduced scale of circuitry and a semiconductor integrated circuit chip which is obtained by integrating the semiconductor circuit and enables chip size reduction are provided. For this purpose, a two-decode method is used. The method uses: a pre-decode circuit comprising a first decoder of the preceding stage which decodes an arbitrary bit of an address signal of eight bits and a second decoder of the preceding stage which decodes the remaining bits; level conversion circuits which shift the output of the pre-decode circuit; and post-decode circuits which decode the decode outputs of the decoders in the pre-decode circuit, level-converted through the level conversion circuits.

Abstract: In a display device such as a liquid crystal display, a processing for compressing a range of display data (grayscale) to a low grayscale side (a grayscale range where response is fast) except for a high grayscale side (a grayscale range where response is slow) at a predetermined compression ratio to conduct display according to response characteristic of transition between grayscales and a temperature state and a processing for increasing a light amount of a backlight to compensate for luminance change due to the compression are performed, for example, in a liquid crystal panel of TN liquid crystal. Thereby, response can be made fast even at a low temperature time.

Abstract: In a display device and a display driver, when a grayscale of a display image is equal to or lower than a specific grayscale value obtained from a histogram of the display image, a display grayscale is extended with a linear function. On the other hand, when a grayscale of a display image is equal to or higher than the specific grayscale value, histogram equalization of a part higher than the specific grayscale value is performed, and the display grayscale is extended with a non-linear function obtained from the histogram equalization.

Abstract: In a display driver, a first backlight control unit using a histogram and a second backlight control unit using an optical sensor can be used in combination. The display driver includes a PWM generating unit setting a control signal value consisting of a product of a luminance rate of X % and a luminance rate of Y % as a luminance rate of a control signal for controlling a backlight with respect to maximum backlight luminance when a luminance rate of a control signal obtained by first backlight control with respect to the maximum backlight luminance is X % and a luminance rate of a control signal obtained by second backlight control with respect to the maximum backlight luminance is Y %.

Abstract: A display brightness control circuit of a liquid crystal display device includes a logarithmic-linear converting circuit for converting an illuminance signal having a logarithmic relationship with incident light into a linear signal. When an output of an external light sensor is a logarithmic signal, the logarithmic signal is converted into a linear signal through the logarithmic-linear converting circuit, and when an output of the external light sensor is a linear signal, the logarithmic-linear converting circuit is not involved. The logarithmic-linear converting circuit corresponds to an exponential circuit which is an inverse function of a logarithm log. Further, when even the same logarithmic output illuminance sensor is different in input-output characteristics, setting of the abovementioned exponential circuit can be changed.

Abstract: In a system including a color liquid crystal panel, a liquid crystal display drive control device for driving the panel, and a microprocessor, the display drive control device of the invention lightens the burden imposed on a microprocessor as well as reduces the power consumption of the system.

Abstract: A liquid crystal driver of liquid crystal display device in which a plurality of expansion/contraction ratios of display data, for example, two kinds of expansion/contraction ratios can be set in a register is provided. Further, the two kinds of expansion/contraction ratios are applicable respectively in two kinds of areas (still-image and video-image) whose coordinates are previously set in a liquid crystal panel. As a result, it is possible to make the still-image area and the video-image area have different expansion/contraction ratios of pixel value respectively. In this manner, it is possible to make display brightness high only in the video-image area, thereby realizing both lower power consumption and visibility improvement at the same time.

Abstract: In a semiconductor integrated circuit device of a liquid crystal display drive controller, the present invention is intended to suppress an increase in the number of output terminals for interface control signals for control of parallel interface to a sub liquid crystal display controller. A host interface circuit comprises a first serial interface circuit for serial data input and output in a differential manner, a parallel interface circuit, and other interface circuits. When the first serial interface circuit is selected for use as the host interface, the host interface circuit outputs in parallel predetermined information input via the first serial interface circuit from the parallel interface circuit to outside and generates interface control signals for the parallel output. External terminals for host interface assigned to the other interface circuits are used for double duty to output the interface control signals.

Abstract: By implementing reduction in power of common electrode voltages applied from a power source of a liquid crystal drive device to common electrode interconnects of a liquid crystal display panel, respectively, reduction in power consumption of the liquid crystal display panel as a whole is attained. A VCOM operation waveform in a charging process from a second voltage VCOML to a first voltage VCOMH shows that a charging current Icha represents the sum of a charging current from VCOML to a reference voltage VCI, Icha1=Cp (VCI?VCOML)/?t, and a charging current from the reference voltage VCI to the first voltage VCOMH, Icha2=Cp (VCOMH?VCI)/?t. Accordingly, power consumed by Icha1 is the reference voltage VCI×Icha1, and power consumed by Icha2 is VCI×Icha2×2.

Abstract: By implementing reduction in power of common electrode voltages applied from a power source of a liquid crystal drive device to common electrode interconnects of a liquid crystal display panel, respectively, reduction in power consumption of the liquid crystal display panel as a whole is attained. A VCOM operation waveform in a charging process from a second voltage VCOML to a first voltage VCOMH shows that a charging current Icha represents the sum of a charging current from VCOML to a reference voltage VCI, Icha1=Cp(VCI-VCOML)/?t, and a charging current from the reference voltage VCI to the first voltage VCOMH, Icha2=Cp(VCOMH?VCI)/?t. Accordingly, power consumed by Icha1 is the reference voltage VCI×Icha1, and power consumed by Icha2 is VCI×Icha2×2.

Abstract: It is aimed at being capable of easily changing a power supply startup procedure and complying with various display devices. A power supply circuit is provided between an instruction register of a liquid crystal driver and a powersupply unit. The power supply unit is not directly supplied with a setting value registered to the instruction register from a microprocessor unit. The microprocessor unit writes setting values to the instruction register without need for the time axis. To turn on the power, the time is measured inside the power supply sequencer. Set values are sequentially input to the power supply unit. The instruction register should be also capable of registering an input timing.