摘要:
A plurality of transistors in which ratios of a channel length L to a channel width W, α=W/L, are different from each other is provided in parallel as output side transistors 105a to 105c in a current mirror circuit 101 which amplifies a photocurrent of a photoelectric conversion device and an internal resistor is connected to each of the output side transistors 105a to 105c in series. The sum of currents which flow through the plurality of transistors and the internal resistor is output, whereby a transistor with large amount of α can be driven in a linear range with low illuminance, and a transistor with small amount of α can be driven in a linear range with high illuminance, so that applicable illuminance range of the photoelectric conversion device can be widened.
摘要翻译:在通过放大光电流的电流镜电路101中,作为输出侧晶体管105a〜105c并联设置多个晶体管,其中沟道长度L与沟道宽度W,α= W / L的比例彼此不同 的一个光电转换装置和一个内部电阻器串联连接到每个输出侧晶体管105a至105c。 输出流过多个晶体管的电流和内部电阻器的总和,由此可以以低照度在线性范围内驱动具有大量α的晶体管,并且可以在a中驱动具有少量α的晶体管 具有高照度的线性范围,可以扩大光电转换装置的适用照度范围。
摘要:
To improve the performance of a protection circuit including a diode formed using a semiconductor film. A protection circuit is inserted between two input/output terminals. The protection circuit includes a diode which is formed over an insulating surface and is formed using a semiconductor film. Contact holes for connecting an n-type impurity region and a p-type impurity region of the diode to a first conductive film in the protection circuit are distributed over the entire impurity regions. Further, contact holes for connecting the first conductive film and a second conductive film in the protection circuit are dispersively formed over the semiconductor film. By forming the contact holes in this manner, wiring resistance between the diode and a terminal can be reduced and the entire semiconductor film of the diode can be effectively serve as a rectifier element.
摘要:
Objects are to accumulate electric charge in a capacitor so that light intensity can be detected even when the amount of incident light is small, and to operate a photoelectric conversion device without increasing the number of elements such as a constant current source or a switch. The photoelectric conversion device includes a photoelectric conversion circuit, a capacitor, and a comparator for comparing a potential of one electrode of the capacitor with a second potential. The photoelectric conversion circuit includes a photoelectric conversion element and an amplifier circuit for amplifying an output current from the photoelectric conversion element In the capacitor, a first potential is supplied through a first switch, and charging or discharging is performed through a second switch in accordance with the current amplified by the amplifier circuit.
摘要:
A protection circuit and a photoelectric conversion device are provided, each of which includes a first wiring, a second wiring, a first switch, a second switch, a capacitor, and a comparing circuit configured to generate a signal corresponding to a potential of the first wiring and a potential of the second wiring, and supply the signal to the first switch and the second switch. The first wiring is electrically connected to a first terminal of the first switch, and the second wiring is electrically connected to a first terminal of the second switch. A second terminal of the first switch is electrically connected to a first electrode of the capacitor, and a second terminal of the second switch is electrically connected to a second electrode of the capacitor.
摘要:
A semiconductor device including a plurality of pixels over a substrate and a display medium including an electronic ink over the substrate, in which at least one pixel of the plurality of pixels comprises first and second subpixels each of which comprises a transistor that comprises an oxide semiconductor including indium, and in which one image of at least one of the plurality of pixels is displayed by a plurality of signals, is provided.
摘要:
Disclosed is a semiconductor device which consumes low power and has high reliability and tolerance for electrostatic discharge. The semiconductor device includes, over a first substrate, a pixel portion and a driver circuit portion both of which have a thin film transistor having an oxide semiconductor layer. The semiconductor device further possesses a second substrate to which a first counter electrode layer and a second counter electrode layer are provided, and a liquid crystal layer is interposed between the first and second substrates. The first and second counter electrode layers are provided over the pixel portion and the driver circuit portion, respectively, and the second counter electrode layer has the same potential as the first counter electrode layer.
摘要:
A semiconductor device has a structure including the first semiconductor region 103 which is provided in the first terminal portion 100 and includes the first n-type impurity region 106, the first resistance region 107 provided at an inner periphery portion of the first n-type impurity region 106 in a plane view, and the first p-type impurity region 108 provided at an inner periphery portion of the first resistance region 107 in the plane view, and the second semiconductor region 104 which is provided in the second terminal portion 101 and includes the second p-type impurity region 109, the second resistance region 110 provided at an inner periphery portion of the second p-type impurity region 109 in the plane view, and the second n-type impurity region 111 provided at an inner periphery portion of the second resistance region 110 in the plane view.
摘要:
A display device which can compensate for variations of the threshold voltage of transistors and suppress variations in luminance, and a driving method thereof are provided. Current is supplied to a light emitting element and light is emitted from the light emitting element by following steps: in the first period initial voltage is stored in a storage capacitor; in the second period, voltage based on video signal voltage and the threshold voltage of the transistor is stored in the storage capacitor; and in the third period, the voltage stored in the storage capacitor in the second period is applied to a gate electrode of the transistor. By these operation processes, the current which compensates the effect of the variations of the threshold voltage of the transistor can be supplied to the light emitting element. Therefore, variations in luminance are suppressed.
摘要:
One feature of the present invention includes first to third steps of holding a voltage, corresponding to a difference between a voltage applied to a first power supply line and a threshold voltage of a first transistor, between both electrodes of first and second storage capacitors; holding a voltage, corresponding to a difference between a voltage applied to the first power supply line and a gate-source voltage of the first transistor, which is necessary to supply a light-emitting element with a current equivalent to a video signal current inputted into a signal line, between both the electrodes of the second storage capacitor; and applying a voltage based on the voltage held in the first and second storage capacitors in the first and second steps to a gate electrode of the first transistor; therefore, a current is supplied to the light-emitting element through the first transistor.
摘要:
One feature of the present invention includes first to third steps of holding a voltage, corresponding to a difference between a voltage applied to a first power supply line and a threshold voltage of a first transistor, between both electrodes of first and second storage capacitors; holding a voltage, corresponding to a difference between a voltage applied to the first power supply line and a gate-source voltage of the first transistor, which is necessary to supply a light-emitting element with a current equivalent to a video signal current inputted into a signal line, between both the electrodes of the second storage capacitor; and applying a voltage based on the voltage held in the first and second storage capacitors in the first and second steps to a gate electrode of the first transistor; therefore, a current is supplied to the light-emitting element through the first transistor.