摘要:
It is an object to suppress deterioration of characteristics of a transistor in a signal line or a scan driver circuit. A first switch for controlling whether to set a potential state of an output signal by being turned on and off in accordance with the first input signal, and a second switch for controlling whether to set a potential state of an output signal by being turned on and off in accordance with the second input signal are included. A first wiring and a second wiring are brought into electrical continuity by turning on and off of the first switch or the second switch.
摘要:
An electroluminescent display device having a configuration hardly generating variations in the current value due to a deteriorated EL element is to be provided. A capacitance element is disposed between the gate and the source of a driving TFT, video signals are inputted to the gate electrode, and then the gate is put in a floating state. At this time, when the gate-source voltage of the driving TFT exceeds its threshold, the driving TFT is turned on. Suppose an EL element is deteriorated and the anode potential rises, that is, the source potential of the driving TFT rises, the potential of the gate electrode of the driving TFT, being in a floating state by coupling with the capacitance element, is to rise by the same amount. Accordingly, even when the anode potential rises due to the deteriorated EL element, the rise is added to the gate electrode potential as it is, and the gate-source voltage of the driving TFT is allowed to be constant.
摘要:
A semiconductor device in which a transistor can supply an accurate current to a load (EL pixel and signal line) without being influenced by variations is provided. A voltage at each terminal of a transistor is adjusted by a feedback circuit using an amplifier circuit. A current Idata is input from a current source circuit to the transistor, and a gate-source voltage is set by the feedback circuit so that the transistor can flow the current Idata. The feedback circuit controls the transistor to operate in a saturation region. Thus, a gate voltage required for flowing the current Idata is set. With the use of the set transistor, a current can be supplied to a load (EL pixel and signal line) with accuracy. Note that a desired gate voltage can be set quickly since the amplifier circuit is utilized.
摘要:
It is an object of the present invention to provide a liquid crystal display device which has a wide viewing angle and less color-shift depending on an angle at which a display screen is seen and can display an image favorably recognized both outdoors in sunlight and dark indoors (or outdoors at night). The liquid crystal display device includes a first portion (161) where display is performed by transmission of light and a second portion (162) where display is performed by reflection of light. Further, a liquid crystal layer (125) includes a liquid crystal molecule which rotates parallel to an electrode plane when a potential difference is generated between two electrodes of a liquid crystal element provided below the liquid crystal layer. The invention is particularly related to the layer structure of electrodes and TFTs (151) arranged on the active matrix substrate (101) of the display device.
摘要:
It is an object of the present invention to provide a liquid crystal display device which has a wide viewing angle and less color-shift depending on an angle at which a display screen is seen and can display an image favorably recognized both outdoors in sunlight and dark indoors (or outdoors at night). The liquid crystal display device includes a first portion (161) where display is performed by transmission of light and a second portion (162) where display is performed by reflection of light. Further, a liquid crystal layer (125) includes a liquid crystal molecule which rotates parallel to an electrode plane when a potential difference is generated between two electrodes of a liquid crystal element provided below the liquid crystal layer. The invention is particularly related to the layer structure of electrodes and TFTs (151) arranged on the active matrix substrate (101) of the display device.
摘要:
The present invention provides a semiconductor device comprising: a transistor; an amplifier circuit; and a current source circuit, wherein one of a source and a drain of the transistor is connected to the current source circuit, wherein a first input terminal of the amplifier circuit is connected to a gate of the transistor, wherein a second input terminal of the amplifier circuit is connected to the one of the source and the drain of the transistor, and wherein an output terminal of the amplifier circuit is connected to the other of the source and the drain of the transistor.
摘要:
A semiconductor device comprising: a first transistor; a capacitor; a first switch; a second switch; a third switch; a fourth switch; and a current source supplying a current to the first transistor and the capacitor, wherein one of a source and a drain of the first transistor is electrically connected to one terminal of the first switch, wherein the other terminal of the first switch is electrically connected to a gate of the first transistor and one terminal of the capacitor, wherein the other terminal of the capacitor is electrically connected to one terminal of the second switch and one terminal of the third switch, and wherein the other terminal of the third switch is electrically connected to the other of the source and the drain of the first transistor and one terminal of the fourth switch.
摘要:
A load, a transistor which controls a current value supplied to the load, a capacitor, a power supply line, and first to third switches are provided. After a threshold voltage of the transistor is held by the capacitor, a potential in accordance with a video signal is inputted and a voltage that is the sum of the threshold voltage and the potential is held. Accordingly, variation in current value caused by variation in threshold voltage of the transistor can be suppressed. Therefore, a desired current can be supplied to a load such as a light emitting element. In addition, a display device with a high duty ratio can be provided by changing a potential of the power supply line.