100results about How to "Reduce drive frequency" patented technology

It is an object to provide a semiconductor display device having a touch panel, which can reduce power consumption. The semiconductor display device includes a panel which is provided with a pixel portion and a driver circuit which controls an input of the image signal to the pixel portion, and a touch panel provided in a position overlapping with the panel in the pixel portion. The pixel portion includes a display element configured to perform display in accordance with voltage of the image signal to be input, and a transistor configured to control retention of the voltage. The transistor includes an oxide semiconductor in a channel formation region. The driving frequency of the driver circuit, that is, the number of writing operations of the image signal for a certain period is changed in accordance with an operation signal from a touch panel.

The invention discloses a bigrid-driven transversely arranged RGBW (Red Green Blue White) pixel structure, a driving method thereof and a display panel. The pixel structure comprises a plurality of pixel units in array repeated permutation, wherein each pixel unit comprises two main pixel areas, eight thin film transistors, two grid lines and four data cables; each main pixel area comprises four subsidiary pixel areas; each data cable is electrically connected with the source electrodes of the two thin film transistors, and different data cables are electrically connected with different thin film transistors; and the grid electrodes of the two thin film transistors electrically connected with the same data cable are respectively in electric connection with different grid lines. According to the embodiment of the invention, when the grid lines of the pixel structure scan pixels in different rows in the same frame, the potential polarity of a signal of each data cable is always unchanged, so that a reversion picture of the pixel points is obtained; and as the polarities of the data cables do not need to be frequently reversed, the driving frequency of the data cables is lowered, and accordingly, the power consumption of a panel is reduced.

A liquid crystal display device comprising a backlight and a pixel portion including first to 2n-th scan lines, wherein, in a first case of expressing a color image, first pixels controlled by the first to n-th scan lines are configured to express a first image using at least one of first to third hues supplied in a first rotating order, and second pixels controlled by the (n+1)-th to 2n-th scan lines are configured to express a second image using at least one of the first to third hues supplied in a second rotating order, wherein, in a second case of expressing a monochrome image, the first and second pixels controlled by the first to 2n-th scan lines are configured to express the monochrome image by external light reflected by the reflective pixel electrode, and wherein the first rotating order is different from the second rotating order.

A transistor whose channel region includes an oxide semiconductor is used as a pull down transistor. The band gap of the oxide semiconductor is 2.0 eV or more, preferably 2.5 eV or more, more preferably 3.0 eV or more. Thus, hot carrier degradation in the transistor can be suppressed. Accordingly, the circuit size of the semiconductor device including the pull down transistor can be made small. Further, a gate of a pull up transistor is made to be in a floating state by switching of on/off of the transistor whose channel region includes an oxide semiconductor. Note that when the oxide semiconductor is highly purified, the off-state current of the transistor can be 1 aA/μm (1×10⁻¹⁸ A/μm) or less. Therefore, the drive capability of the semiconductor device can be improved.

An organic light emitting display is capable of reducing power consumption. The organic light emitting display includes a scan driver for sequentially supplying scan signals to scan lines, a data driver for supplying data signals to data lines in synchronization with the scan signals, pixels located at crossing regions of the scan lines and the data lines, a timing controller for determining a normal driving mode for displaying a normal image and a standby driving mode displaying less information than the normal image, and a power source for supplying a first power and a second power to the pixels, wherein a voltage difference between the first power and the second power in the normal driving mode is a first voltage, and a voltage difference between the first power and the second power is a second voltage different from the first voltage.

The invention discloses an LED backlight driving circuit. The LED backlight driving circuit comprises a boosting circuit, a current control module, a driving chip, a current detection module, a control signal module and a frequency adjusting module, wherein the boosting circuit is used for converting an input voltage into a required output voltage and providing the output voltage for an LED string light, the current control module is connected to the negative end of the LED string light and used for adjusting the working current of the LED string light, the driving chip is used for providing a first square-wave signal for the boosting circuit and providing a second square-wave signal for the current control module, the current detection module is used for detecting the working current of the LED string light and generating a detection signal, the control signal module receives the detection signal generated by the current detection module and generates a control signal, the frequency adjusting module receives the control signal generated by the control signal module and generates a resistance value according to the control signal, the frequency adjusting module is further connected to the driving chip, and the driving chip adjusts the driving frequency of the backlight driving circuit according to the resistance value. The invention further discloses a liquid crystal display with the backlight driving circuit.

A device of driving a light source for a display device is provided, which includes: a temperature sensor detecting a temperature near the light source; and an inverter controlling the light source depending on temperature information supplied from the temperature sensor. The inverter adjusts either or both of a driving frequency and a driving current of the light source depending on the temperature information. The inverter decreases the driving frequency when the detected temperature is lower than a first temperature, and the inverter increases the driving current when the detected temperature is lower than a second temperature lower than the first temperature.

The embodiment of the invention discloses a pixel circuit and a display device. The pixel circuit comprises a data voltage write-in module, a driving module, a storage module, a light emitting module and a leakage current suppression module. The data voltage write-in module is used for writing data voltage into the control end of the driving module. The storage module is used for storing data voltage of the control end of the driving module. The driving module is used for driving the light-emitting module to emit light according to the data voltage of the control end of the driving module. The leakage current suppression module is electrically connected with the control end of the driving module and is used for maintaining the potential of the control end of the driving module. The potential of the control end of the driving module is not easy to release in the light emitting stage, so that the potential of the control end of the driving module can be well maintained, and the display effect is improved. Moreover, the driving frequency of the pixel circuit can be reduced, and the power consumption of the whole display device comprising the pixel circuit is reduced. And the area of the storage module can be reduced, so that the pixel density can be improved.

An object of the present invention is to reduce the number of necessary terminals on a substrate, realize data transmission resistant to disturbance noise even when a source voltage of a logic system for processing a digital video signal is lowered, reduce an influence of a radiated noise, and provide an output image of high picture quality. For that purpose, a reflection type of liquid crystal display has a silicon substrate 1 as an active matrix substrate, uses the digital video signal for a video signal to be input, and converts the digital video signal into an analog video signal in the silicon substrate 1 to provide the output image. The reflection type of liquid crystal display having the above configuration has a DAC circuit 22 for converting the input digital video signal into the analog video signal; and an LVDS receiver 20 which receives each digital video signal that is to be input into the DAC circuit 22, through a LVDS transmission. The LVDS receiver 20 is mounted on the same silicon substrate 1 as the DAC circuit 22 is mounted.

The following semiconductor device provides high reliability and a narrower frame width. The semiconductor device includes a driver circuit and a pixel portion. The driver circuit has a first transistor including a first gate and a second gate electrically connected to each other with a semiconductor film sandwiched therebetween, and a second transistor electrically connected to the first transistor. The pixel portion includes a third transistor, a liquid crystal element, and a capacitor. The liquid crystal element includes a first transparent conductive film electrically connected to the third transistor, a second conductive film, and a liquid crystal layer. The capacitor includes the first conductive film, a third transparent conductive film, and a nitride insulating film. The nitride insulating film is positioned between the first transparent conductive film and the third transparent conductive film, and positioned between the semiconductor film and the second gate of the first transistor.

A fuel vapor treatment system is mounted on a hybrid vehicle having an internal combustion engine and an electric motor. Even when an internal combustion engine is stopped, a discharge of fuel vapor from a first canister to atmosphere can be detected. When the discharge of the fuel vapor from the first canister is detected, the internal combustion engine is started to perform a purge process. When it is detected that the purge process in the first canister is finished, the internal combustion engine is stopped to terminate the purge process.

Disclosed herewith is a matrix driving method of liquid crystal which exhibits a cholesteric phase. In the method, there is a selection pulse application step of applying pulses to select the final state of the liquid crystal, and between the selection pulse application step of a scanning line and the selection pulse application step of the next scanned scanning line, a delay step is inserted. During the delay step, a signal pulse is of 0V or of a pulse voltage for a display of a specified density.

Liquid is ejected in a pulse-like manner from a nozzle provided at the distal end of a liquid ejection pipe. When the liquid is ejected, moving speed of the nozzle is detected. A driving frequency of a piezoelectric element is increased when the moving speed increase. The driving frequency is reduced when the moving speed decreases. Consequently, it is possible to prevent the number of times the liquid is ejected per unit length from changing according to the moving speed of the nozzle. Therefore, it is possible to excise a biological tissue at stable excision depth.

This disclosure relates to a technique for smoothly carrying out an acceleration operation and a deceleration operation for a vibration type actuator to prevent a situation where in starting the vibration type actuator, a drive frequency is reduced to become lower than a resonance frequency to stop the vibration type actuator. A first counter performs up-count from a first value to a second value larger than the first value at predetermined time intervals in accelerating the vibration type actuator. A rate multiplier outputs a clock signal having a frequency corresponding to the count value. A second counter measures a period of a pulse signal, the period being adapted to change in correspondence to a drive speed of the vibration type actuator, by counting the clock pulses. The drive speed of the vibration type actuator is controlled such that the measured pulse period becomes a predetermined target value.

The organic light emitting display includes a plurality of pixels positioned at intersections of scan lines, emission control lines, and data lines, a scan driver for sequentially supplying scan signals to the scan lines at a first driving frequency in order to select the pixels in units of horizontal lines, and an emission driver for sequentially supplying emission control signals to the emission control lines at a second driving frequency different from the first driving frequency in order to control emission of the pixels.

A shift register, gate drive circuit and display panel are provided. The shift register includes a latch unit, a NAND gate unit, a buffer unit and a switch unit. The latch unit, the NAND gate unit and the buffer unit are configured to produce a scanning driving signal and a scanning stopping signal. The latch unit is configured to control the switch unit to be turned on so as to output the scanning driving signal or the scanning stopping signal from the output terminal of the shift register, or control the switch unit to be turned off so as to enable the output terminal of the shift register to float.