Abstract:
An object is to provide a semiconductor device with a novel structure. The semiconductor device includes a first wiring; a second wiring; a third wiring; a fourth wiring; a first transistor having a first gate electrode, a first source electrode, and a first drain electrode; and a second transistor having a second gate electrode, a second source electrode, and a second drain electrode. The first transistor is provided in a substrate including a semiconductor material. The second transistor includes an oxide semiconductor layer.
Abstract:
An inexpensive display device, as well as an electrical apparatus employing the same, can be provided. In the display device in which a pixel section and a driver circuit are included on one and the same insulating surface, the driver circuit includes a decoder 100 and a buffer section 101. The decoder 100 includes a plurality of NAND circuits each including p-channel TFTs 104 to 106 connected to each other in parallel and other p-channel TFTs 107 to 109 connected to each other in series. The buffer section 101 includes a plurality of buffers each including three p-channel TFTs 114 to 116.
Abstract:
The amplitude voltage of a signal input to a level shifter can be increased and then output by the level shifter circuit. Specifically, the amplitude voltage of the signal input to the level shifter can be increased to be output. This decreases the amplitude voltage of a circuit (a shift register circuit, a decoder circuit, or the like) which outputs the signal input to the level shifter. Consequently, power consumption of the circuit can be reduced. Alternatively, a voltage applied to a transistor included in the circuit can be reduced. This can suppress degradation of the transistor or damage to the transistor.
Abstract:
There are provided a structure of a semiconductor device in which low power consumption is realized even in a case where a size of a display region is increased to be a large size screen and a manufacturing method thereof. A gate electrode in a pixel portion is formed as a three layered structure of a material film containing mainly W, a material film containing mainly Al, and a material film containing mainly Ti to reduce a wiring resistance. A wiring is etched using an IPC etching apparatus. The gate electrode has a taper shape and the width of a region which becomes the taper shape is set to be 1 μm or more.
Abstract:
A step for forming an island-shaped semiconductor layer of a semiconductor device used in a display device is omitted in order to manufacture the semiconductor device with high productivity and low cost. The semiconductor device is manufactured through four photolithography processes: four steps for forming a gate electrode, for forming a source electrode and a drain electrode, for forming a contact hole, and for forming a pixel electrode. In the step for forming the contact hole, a groove portion in which a semiconductor layer is removed is formed, whereby formation of a parasitic transistor is prevented. An oxide semiconductor is used as a material of the semiconductor layer in which a channel is formed, and an oxide semiconductor having a higher insulating property than the semiconductor layer is provided over the semiconductor layer.
Abstract:
To provide a semiconductor device with such a new structure that the effect of variation in transistor characteristics can be reduced to achieve less variation in the output voltage of a memory cell. A memory cell includes a source follower (common drain) transistor for reading data held in a gate. A voltage applied to a transistor generating a reference current flowing through the memory cell is determined so that a gate-source voltage is approximately equal to the threshold voltage of the transistor. With such a structure, data stored in the memory cell can be read as a voltage that is less influenced by variation of transistors such as the field-effect mobility and the size.
Abstract:
A current source circuit includes current sources that are each configured to receive an external set signal and to control an output current value based on the external set signal. A changing over circuit that is electrically connected to the current sources and a set of output lines selects one of the current sources to be electrically connected to each of the output lines.
Abstract:
To provide a power storage device, an operation condition of which is easily analyzed. A secondary battery includes a sensor that is a measurement unit, a microcontroller unit that is a determination unit, and a memory that is a memory unit. With the sensor, conditions of the secondary battery such as the remaining battery power, the voltage, the current, and the temperature are measured. The microcontroller unit performs arithmetic processing of the measurement results and determines the operation condition of the secondary battery. Further, the microcontroller unit stores the measurement result in the memory in accordance with the operation condition of the secondary battery.
Abstract:
An inexpensive display device, as well as an electrical apparatus employing the same, can be provided. In the display device in which a pixel section and a driver circuit are included on one and the same insulating surface, the driver circuit includes a decoder 100 and a buffer section 101. The decoder 100 includes a plurality of NAND circuits each including p-channel TFTs 104 to 106 connected to each other in parallel and other p-channel TFTs 107 to 109 connected to each other in series. The buffer section 101 includes a plurality of buffers each including three p-channel TFTs 114 to 116.
Abstract:
A novel method for driving a display device in which generation of flickers caused by rewriting pixels is reduced and which has a high aperture ratio is provided. The driving method includes a first step of determining whether displayed still image data is two-valued still image data or multivalued still image data, and a second step of performing display by rewriting (refreshing) the two-valued still image data with lower frequency than the multivalued still image data.