摘要:
A semiconductor device with less power consumption and an electronic appliance using the same. The semiconductor device of the invention is supplied with a first potential from a high potential power source and a second potential from a low potential power source. Upon input of a first signal to an input node, an output node outputs a second signal. With the semiconductor device of the invention, a potential difference of the second signal can be controlled to be smaller than a potential difference between the first potential and the second potential, thereby power consumption required for charging/discharging wires can be reduced.
摘要:
A light-emitting element has a property that a resistance value (internal resistance) changes in accordance with an environmental temperature. It is an object to downsize a monitoring element which corrects an influence of variations in current value of the light-emitting element, which are caused by an environmental temperature change and a change with time. A pixel includes a plurality of sub-pixels, areas of light-emitting elements provided in the individual sub-pixels are made to be different from each other, and an area of a monitoring element is made to be the same as an area of the light-emitting element in any of the sub-pixels, thereby correcting light-emission of the pixel by the monitoring element.
摘要:
Outside light is received using a light sensor, and in accordance with the outside light intensity, each of a first display mode which expresses multiple gray scales and a second display-y mode which expresses a gray scale smaller in number than that in the first display mode is switched and used. The switching is controlled by a display controller based on data of the outside light intensity. Accordingly, the visibility can be ensured in a wide range of situations, from under a fluorescent lamp in a dark place or inside, to under sunlight outside. In the second display mode, frequencies of a start pulse and a clock pulse to be inputted to a source signal line driver circuit are reduced and a driving voltage is decreased by the display controller; accordingly, a frame period can be longer than that in the first display mode and power consumption can be reduced.
摘要:
Semiconductor elements deteriorate or are destroyed due to electrostatic discharge damage. The present invention provides a semiconductor device in which a protecting means is formed in each pixel. The protecting means is provided with one or a plurality of elements selected from the group consisting of resistor elements, capacitor elements, and rectifying elements. Sudden changes in the electric potential of a source electrode or a drain electrode of a transistor due to electric charge that builds up in a pixel electrode is relieved by disposing the protecting means between the pixel electrode of the light-emitting element and the source electrode or the drain electrode of the transistor. Deterioration or destruction of the semiconductor element due to electrostatic discharge damage is thus prevented.
摘要:
A light emitting device comprising a light emitting element and a first transistor and a second transistor controlling current to be supplied to the light emitting element in a pixel; the first transistor is normally-on; the second transistor is normally-off; a channel length of the first transistor is longer than a channel width thereof; a channel length of the second transistor is equal to or shorter than a channel length thereof; gate electrodes of the first transistor and the second transistor are connected to each other; the first transistor and the second transistor have the same polarity; and the light emitting element, the first transistor and the second transistor are all connected in series.
摘要:
The present invention provides a data latch circuit which can operate stably with a low-amplitude signal, which consumes less electric power, and which is resistant against the variation in TFTs. When an analog switch is turned on, a data signal is inputted to a gate electrode of an n-channel TFT and, at this time, VDD is supplied to an input terminal of an inverter. When the analog switch in turned off, the n-channel TFT is turned on or off depending on a level of the data signa. When the data signal is at an H level, the n-channel TFT is turned on and VSS is supplied to the input terminal of the inverter. When the data signal is at an L level, VDD is supplied to an input terminal of the inverter. Therefore, only VDD and VSS levels are applied to the input terminal of the inverter.
摘要:
If the frequency of a clock signal is increased, the pulse width of a sampling pulse is decreased, and the amount of time for a video signal to be written to a source line is inadequate. Sampling pulses (sam) rise sequentially in synchronization with the rise of a start pulse (SP). As the start pulse (SP) rises, synchronized with the rise of clock signals (CK, CKB), the sampling pulses (sam) fall off sequentially, delayed by half the period of the clock signals (CK, CKB) for every step. As a result, the sampling pulses (sam) with a pulse width longer than one period of the clock signals (CK, CKB) are generated. In a period Ta, a desired video signal (VIDEO) is written to its corresponding source line. In this way, the time for half a period of the clock signal can be secured for writing to the source line.
摘要:
A display device capable of displaying a picture of vivid colors maintaining a good balance of colors and a good balance of light-emitting brightnesses of the EL elements. The widths of the detour wirings supplying current to the power source feed lines are increased for those EL elements into which a current of a large density flows. This constitution decreases the wiring resistances of the detour wirings, decreases the potential drop through the detour wirings, and suppresses the amount of electric power consumed by the detour wirings.
摘要:
A display device according to the present invention includes: a planarization layer for insulating between a gate electrode etc. and a data wiring, a drain electrode, or the like of the transistor; and a barrier layer that is formed on an upper surface or lower surface of the planarization layer and at the same time, adapted to suppress diffusion of moisture or degassing components from the planarization layer. The display device adopts a device structure effective in reducing the plasma damage on the planarization layer by devising a positional relationship between the planarization layer and the barrier layer. Also, in combination with a novel structure as a structure for a pixel electrode, effects such as an increase in luminance can be provided as well.
摘要:
A light emitting device comprising a light emitting element and a first transistor and a second transistor controlling current to be supplied to the light emitting element in a pixel; the first transistor is normally-on; the second transistor is normally-off; a channel length of the first transistor is longer than a channel width thereof; a channel length of the second transistor is equal to or shorter than a channel length thereof; gate electrodes of the first transistor and the second transistor are connected to each other; the first transistor and the second transistor have the same polarity; and the light emitting element, the first transistor and the second transistor are all connected in series.