Abstract:
A display device includes first and second display elements, first to fourth transistors, and a first insulating layer. The first insulating layer is positioned between the second display element, the third transistor, the fourth transistor, the first display element, the first transistor, and the second transistor. The second display element has a function of emitting a second light on the first insulating layer side. The first display element has a function of emitting a first light to the same direction as the second light.
Abstract:
To provide a display device in which a reflective liquid crystal element and a light-emitting element are switched for display, and the operation of a reflective liquid crystal element driver IC and the operation of a light-emitting element driver IC can be alternately stopped even when they are integrated. The display device includes a pixel, a driver circuit, and a switching control circuit. The driver IC includes a buffer amplifier for outputting a grayscale voltage to drive the liquid crystal element and a buffer amplifier for outputting a grayscale voltage to drive the light-emitting element. Each buffer amplifier includes a transistor configured to supply a bias current, and a switch. The switch is configured to control a conduction state between a wiring for supplying a bias voltage and a gate of the transistor. The switching control circuit is configured to output a switching signal for controlling a conduction state of the switch.
Abstract:
Disclosed is a signal processing circuit including an analog-to-digital converter, an arithmetic processing unit electrically connected to the analog-to-digital converter, and a first register electrically connected to the arithmetic processing unit. The extremely small off-state current of a transistor included in the first register allows the first register to retain a signal output from the arithmetic processing unit. This structure enables stationary driving of a load even if the signal processing circuit is turned off, which contributes to a reduction in power consumption of an electronic device having the load.
Abstract:
Disclosed is a power storage unit which can safely operate over a wide temperature range. The power storage unit includes: a power storage device; a heater for heating the power storage device; a temperature sensor for sensing the temperature of the power storage device; and a control circuit configured to inhibit charge of the power storage device when its temperature is lower than a first temperature or higher than a second temperature. The first temperature is exemplified by a temperature which allows the formation of a dendrite over a negative electrode of the power storage device, whereas the second temperature is exemplified by a temperature which causes decomposition of a passivating film formed over a surface of a negative electrode active material.
Abstract:
A semiconductor device having a novel structure is provided. Fluctuation in the grayscale voltage due to an offset voltage is suppressed. When a current corresponding to a lower-bit grayscale voltage is generated in a transconductance amplifier, voltages VHI and VLO supplied to the transconductance amplifier are alternately input to two input terminals in accordance with a digital signal of the most significant bit of lower bits. Since a change corresponding to the offset voltage is added to both the maximum and minimum values of the current output from the transconductance amplifier, fluctuation in the grayscale voltage due to the offset voltage can be suppressed.
Abstract:
An object of the present invention is to suppress deterioration in the thin film transistor. A plurality of pulse output circuits each include first to eleventh thin film transistors is formed. The pulse output circuit is operated on the basis of a plurality of clock signals which control each transistor, the previous stage signal input from a pulse output circuit in the previous stage, the next stage signal input from a pulse output circuit in the next stage, and a reset signal. In addition, a microcrystalline semiconductor is used for a semiconductor layer serving as a channel region of each transistor. Therefore, degradation of characteristics of the transistor can be suppressed.
Abstract:
To provide a control circuit in a DC-DC converter, which includes transistors with the same conductivity type. The control circuit generates a pulse signal (GS), and includes a hysteresis comparator, a logic unit, a digital-analog converter circuit, and a comparator. The hysteresis comparator converts a signal (FB) based on an output voltage of the DC-DC converter into a digital signal (comp). The logic unit generates, in accordance with the signal comp, a pulse width modulation signal (pwm) determining a pulse width of the signal GS. The logic unit also divides a reference clock signal to generate an m-bit (m is greater than or equal to 2) second digital signal. The digital-analog converter circuit converts the m-bit second digital signal into an analog signal to generate a 2m-level triangular wave signal. The comparator compares the signal pwm with the triangular wave signal to output the comparison result as the signal GS.
Abstract:
Degradation of a secondary battery or the like is prevented. A reduction in the capacity of a secondary battery or the like due to charging or discharging is prevented. A secondary battery module in which a secondary battery can be charged in a charging period into which short discharging periods are inserted is provided. A secondary battery module in which a plurality of secondary batteries are connected in parallel, and in a charging period of the secondary batteries, current due to short-time discharging of one secondary battery can be used for charging another secondary battery is provided. To carry out such operation, a secondary battery module includes a plurality of secondary batteries, a DC/DC converter, a switch, and a control circuit.
Abstract:
An object is to inhibit a decrease in the capacity of a power storage device or to compensate the capacity, by adjusting or rectifying an imbalance between a positive electrode and a negative electrode, which is caused by decomposition of an electrolyte solution at the negative electrode. Provided is a charging method of a power storage device including a positive electrode using an active material that exhibits two-phase reaction, a negative electrode, and an electrolyte solution. The method includes the steps of, after constant current charging, performing constant voltage charging with a voltage that does not cause decomposition of the electrolyte solution until a charging current becomes lower than or equal to a lower current value limit; and after the constant voltage charging, performing additional charging with a voltage that causes decomposition of the electrolyte solution until a resistance of the power storage device reaches a predetermined resistance.
Abstract:
A display device that is suitable for increasing its size is provided. The display device includes first to third wirings, a first transistor, first to third conductive layers, and a first pixel electrode; the first wiring extends in a first direction and intersects with the second and the third wirings; the second and the third wirings each extend in a second direction intersecting with the first direction; a gate of the first transistor is electrically connected to the first wiring; one of a source and a drain of the first transistor is electrically connected to the second wiring through the first to the third conductive layers; the second conductive layer includes a region overlapping with the third wiring; the first conductive layer, the third conductive layer, and the first pixel electrode contain the same material; the first wiring and the second conductive layer contain the same material; the first wiring is supplied with a selection signal; and the second and the third wirings are supplied with different signals.