Patent application number | Description | Published |
20080308792 | DISPLAY DEVICE - A single-crystal semiconductor layer which is separated from a single-crystal semiconductor substrate, and bonded to and provided over a supporting substrate is used, whereby a transistor having uniform characteristics can be formed. A reference circuit having a bipolar transistor is provided, whereby temperature dependence of a driving transistor which is driven by supplying current to the light-emitting element of a pixel is compensated. | 12-18-2008 |
20090140270 | DISPLAY DEVICE AND METHOD FOR MANUFACTURING THEREOF - An object is to provide a system-on-panel display device including a display portion and a peripheral circuit for controlling display on the display portion over one substrate, which can operate more accurately. The display device has a display portion provided with a pixel portion including a plurality of pixels and a peripheral circuit portion for controlling display on the display portion, which are provided over a substrate. Each of the display portion and the peripheral circuit portion includes a plurality of transistors. For semiconductor layers of the transistors, single crystal semiconductor materials are used. | 06-04-2009 |
20090159890 | Semiconductor Display Device - A semiconductor display device using a light-emitting element, which can suppress luminance unevenness among pixels due to the potential drop of a wiring, is provided. Power supply lines to which a power supply potential is supplied are electrically connected to each other in a display region where a plurality of pixels are arranged. Further, an interlayer insulating film is formed over a wiring (an auxiliary power supply line) for electrically connecting the power supply lines to each other in the display region and a gate electrode of a transistor included in a pixel; and the power supply lines are formed over the interlayer insulating film which is formed over the auxiliary power supply line and the gate electrode. Furthermore, a wiring (an auxiliary wiring) formed over the interlayer insulating film is electrically or directly connected to the auxiliary power supply line. | 06-25-2009 |
20100085030 | Semiconductor Device and RFID Tag Using the Semiconductor Device - A semiconductor device monitors a voltage between a reference potential and an input potential and obtains a constant output potential regardless of a value of the voltage, after the voltage exceeds a predetermined threshold voltage in such a manner that the semiconductor device divides a voltage between the reference potential and the input potential using a plurality of first non-linear elements and at least one linear element to constantly generate a first bias voltage regardless of a value of the voltage, divides a voltage between the reference potential and the input potential using a plurality of second non-linear elements with reference to the first bias voltage to constantly generate a second bias voltage regardless of a value of the voltage, and determines the output potential with reference to the second bias voltage. | 04-08-2010 |
20100201659 | PULSE OUTPUT CIRCUIT, DISPLAY DEVICE, AND ELECTRONIC DEVICE - 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. | 08-12-2010 |
20110084263 | SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD THEREOF - It is an object to provide a semiconductor device having a new productive semiconductor material and a new structure. The semiconductor device includes a first conductive layer over a substrate, a first insulating layer which covers the first conductive layer, an oxide semiconductor layer over the first insulating layer that overlaps with part of the first conductive layer and has a crystal region in a surface part, second and third conductive layers formed in contact with the oxide semiconductor layer, an insulating layer which covers the oxide semiconductor layer and the second and third conductive layers, and a fourth conductive layer over the insulating layer that overlaps with part of the oxide semiconductor layer. | 04-14-2011 |
20110089414 | SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD THEREOF - An object is to reduce leakage current and parasitic capacitance of a transistor used for an LSI, a CPU, or a memory. A semiconductor integrated circuit such as an LSI, a CPU, or a memory is manufactured using a thin film transistor in which a channel formation region is formed using an oxide semiconductor which becomes an intrinsic or substantially intrinsic semiconductor by removing impurities which serve as electron donors (donors) from the oxide semiconductor and has larger energy gap than that of a silicon semiconductor. With use of a thin film transistor using a highly purified oxide semiconductor layer with sufficiently reduced hydrogen concentration, a semiconductor device with low power consumption due to leakage current can be realized. | 04-21-2011 |
20110101331 | SEMICONDUCTOR DEVICE - An object is to reduce leakage current and parasitic capacitance of a transistor used for an LSI, a CPU, or a memory. A semiconductor integrated circuit included in an LSI, a CPU, or a memory is manufactured using the transistor which is formed using an oxide semiconductor which is an intrinsic or substantially intrinsic semiconductor obtained by removal of impurities which serve as electron donors (donors) from the oxide semiconductor and has larger energy gap than a silicon semiconductor, and is formed over a semiconductor substrate. With the transistor which is formed over the semiconductor substrate and includes the highly purified oxide semiconductor layer with sufficiently reduced hydrogen concentration, a semiconductor device whose power consumption due to leakage current is low can be realized. | 05-05-2011 |
20110101942 | VOLTAGE REGULATOR CIRCUIT - A voltage regulator circuit includes a transistor and a capacitor. The transistor includes a gate, a source, and a drain, a first signal is inputted to one of the source and the drain, a second signal which is a clock signal is inputted to the gate, an oxide semiconductor layer is used for a channel formation layer, and an off-state current is less than or equal to 10 aA/μm. The capacitor includes a first electrode and a second electrode, the first electrode is electrically connected to the other of the source and the drain of the transistor, and a high power source voltage and a low power source voltage are alternately applied to the second electrode. | 05-05-2011 |
20110115839 | DISPLAY DEVICE AND ELECTRONIC DEVICE INCLUDING THE SAME - A display device includes a pixel portion including a plurality of pixels each including a first transistor, a second transistor, and a light-emitting element, in which a gate of the first transistor is electrically connected to a scan line, one of a source and a drain of the first transistor is electrically connected to a signal line, and the other of them is electrically connected to a gate of the second transistor; one of a source and a drain of the second transistor is electrically connected to a power supply line and the other of them is electrically connected to the light-emitting element, and the first transistor includes an oxide semiconductor layer. A period when the display device displays a still image includes a period in which output of a signal to all the scan lines in the pixel portion is stopped. | 05-19-2011 |
20110133706 | DC CONVERTER CIRCUIT AND POWER SUPPLY CIRCUIT - A DC converter circuit having high reliability is provided. The DC converter circuit includes: an inductor configured to generate electromotive force in accordance with a change in flowing current; a transistor including a gate, a source, and a drain, which is configured to control generation of the electromotive force in the inductor by being on or off; a rectifier in a conducting state when the transistor is off; and a control circuit configured to control on and off of the transistor. The transistor includes an oxide semiconductor layer whose hydrogen concentration is less than or equal to 5×10 | 06-09-2011 |
20110249786 | DIVIDER CIRCUIT - A divider circuit includes a shift register which generates 2X (X is a natural number greater than or equal to 2) pulse signals in accordance with a first clock signal or a second clock signal and outputs them, and a divided signal output circuit which generates a signal to be a third clock signal with a cycle X times longer than a cycle of the first clock signal in accordance with the 2X pulse signals and outputs it. The divided signal output circuit includes X first transistors which control whether voltage of the signal to be the third clock signal is set to first voltage; and X second transistors which control whether voltage of the signal to be the third clock signal is set to second voltage. | 10-13-2011 |
20110266564 | SEMICONDUCTOR DISPLAY DEVICE - A semiconductor display device using a light-emitting element, which can suppress luminance unevenness among pixels due to the potential drop of a wiring, is provided. Power supply lines to which a power supply potential is supplied are electrically connected to each other in a display region where a plurality of pixels are arranged. Further, an interlayer insulating film is formed over a wiring (an auxiliary power supply line) for electrically connecting the power supply lines to each other in the display region and a gate electrode of a transistor included in a pixel; and the power supply lines are formed over the interlayer insulating film which is formed over the auxiliary power supply line and the gate electrode. Furthermore, a wiring (an auxiliary wiring) formed over the interlayer insulating film is electrically or directly connected to the auxiliary power supply line. | 11-03-2011 |
20110285372 | SEMICONDUCTOR DEVICE AND DISPLAY DEVICE - An object is to reduce power consumption of a semiconductor device including a DC-DC converter circuit. The semiconductor device includes a DC-DC converter circuit and a microprocessor. The DC-DC converter circuit includes a conversion circuit including an inductor and a transistor, and a control circuit including a comparison circuit and a logic circuit. A hysteresis comparator is used as the comparison circuit. In the control circuit, the comparison circuit compares an output signal of the conversion circuit with a first reference potential or a second reference potential, and the logic circuit performs arithmetic operation between an output signal of the comparison circuit and a clock signal of the microprocessor. In the conversion circuit, the transistor controls current flowing through the inductor in accordance with an output signal of the logic circuit, and the output signal of the conversion circuit is generated in accordance with the current flowing through the inductor. | 11-24-2011 |
20110285426 | SEMICONDUCTOR DEVICE AND DISPLAY DEVICE - An object is to reduce power consumption of a semiconductor device including a DC-DC converter circuit. The semiconductor device includes a DC-DC converter circuit and a microprocessor. The DC-DC converter circuit includes a conversion circuit including an inductor and a transistor, and a control circuit including a comparison circuit and a logic circuit. In the control circuit, the comparison circuit compares an output of the conversion circuit and a reference value, and the logic circuit performs an arithmetic operation between an output of the comparison circuit and a clock signal of the microprocessor. In the conversion circuit, the transistor controls a current flowing through the inductor in accordance with an output of the logic circuit, and the output of the conversion circuit is generated in accordance with the current flowing through the inductor. | 11-24-2011 |
20110304311 | DC/DC CONVERTER, POWER SUPPLY CIRCUIT, AND SEMICONDUCTOR DEVICE - Provided is a DC-DC converter with improved power conversion efficiency. A transistor which is incorporated in the DC-DC converter and functions as a switching element for controlling output power includes, in its channel formation region, a semiconductor material having a wide band gap and significantly small off current compared with silicon. The transistor further comprises a back gate electrode, in addition to a general gate electrode, and a back gate control circuit for controlling a potential applied to the back gate electrode in accordance with the output power from the DC-DC converter. The control of the potential applied to the back gate electrode by the back gate control circuit enables the threshold voltage to decrease the on-state resistance when the output power is high and to increase the off-state current when the output power is low. | 12-15-2011 |
20120032606 | Light-Emitting Device - The amplitude of a potential of a signal line is decreased and a scan line driver circuit is prevented from being excessively loaded. A light-emitting device includes a light-emitting element; a first power supply line having a first potential; a second power supply line having a second potential; a first transistor for controlling a connection between the first power supply line and the light-emitting element; a second transistor, which is controlled in accordance with a video signal, whether outputting the second potential applied from the second power supply line or not; a switching element for selecting either the first potential applied from the first power supply line or the output of the second transistor; and a third transistor for selecting whether the first potential or the output of the second transistor which is selected by the switch is applied to a gate of the first transistor. | 02-09-2012 |
20120042926 | Photoelectric Conversion Module and Manufacturing Method Thereof - A photoelectric conversion module in which an output voltage defect is suppressed is obtained by forming in parallel over a substrate n number (n is a natural number) of integrated photoelectric conversion devices each including a plurality of cells that are connected in series, and electrically connecting in parallel n−1 number or less of integrated photoelectric conversion devices with normal electrical characteristics and excluding an integrated photoelectric conversion device with a characteristic defect such as a short-circuit between top and bottom electrodes or a leak current due to a structural defect or the like formed in a semiconductor layer or the like. | 02-23-2012 |
20120043911 | Lighting Device - A lighting device whose power conversion efficiency is improved by suppression of fluctuation in luminance of a light-emitting element and deterioration of the light-emitting element due to a change in temperature and a change over time and whose power consumption is reduced is provided. The disclosed invention is a lighting device that has a function of correcting a change in temperature and a change over time and includes at least one switching regulator in a driver portion. Constant current drive is performed on light-emitting elements and monitor light-emitting elements are used, so that highly-efficient output voltage which is corrected to have an optimal level is applied to the light-emitting elements and stable drive is performed for a long time. Power conversion efficiency is improved by a switching regulator, so that the total power consumption of the lighting device is reduced. | 02-23-2012 |
20120104862 | PHOTOELECTRIC CONVERSION DEVICE - A photoelectric conversion device includes at least two photoelectric conversion elements which have voltage-current characteristics different from each other. Further, one of the photoelectric conversion elements has photoelectric conversion efficiency higher than that of the other photoelectric conversion element under the environment in which room light can be obtained. Furthermore, the other photoelectric conversion element has photoelectric conversion efficiency higher than the one of the photoelectric conversion elements under the environment in which sunlight can be obtained. Moreover, each of the voltage of electric power generated in the at least two photoelectric conversion elements is adjusted by one of at least two DC-DC converters corresponding the photoelectric conversion element. In addition, part of the electric power generated in the one of the photoelectric conversion elements is used as drive electric power of the at least two DC-DC converter. | 05-03-2012 |
20120140523 | DC-DC CONVERTER AND MANUFACTURING METHOD THEREOF - A DC-DC converter is driven by single high input voltage, and includes a voltage converter circuit and a control circuit. The increase of the occupied area of the DC-DC converter is suppressed. The DC-DC converter includes an input terminal to which input voltage is applied; a voltage converter circuit connected to the input terminal, and including a first transistor; a control circuit configured to control the voltage converter circuit, and including a second transistor including a silicon material in a channel formation region; and a third transistor provided between the input terminal and the control circuit, and configured to convert the input voltage into power supply voltage that is lower than the input voltage. The first transistor and the third transistor include an oxide semiconductor material in channel formation regions. The first transistor and the third transistor are stacked over the second transistor with an insulating film provided therebetween. | 06-07-2012 |
20120182208 | DISPLAY DEVICE AND METHOD FOR MANUFACTURING THEREOF - An object is to provide a system-on-panel display device including a display portion and a peripheral circuit for controlling display on the display portion over one substrate, which can operate more accurately. The display device has a display portion provided with a pixel portion including a plurality of pixels and a peripheral circuit portion for controlling display on the display portion, which are provided over a substrate. Each of the display portion and the peripheral circuit portion includes a plurality of transistors. For semiconductor layers of the transistors, single crystal semiconductor materials are used. | 07-19-2012 |
20130093025 | PULSE OUTPUT CIRCUIT, DISPLAY DEVICE, AND ELECTRONIC DEVICE - 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. | 04-18-2013 |
20130147365 | Light-Emitting Device and Method of Driving Light-Emitting Device - Reduction of luminance dispersion of a plurality of light-emitting panels combined into one light-emitting device is achieved by the use of a new light-emitting device which has a photosensor, a plurality of light-emitting panels, DC/DC converters connected to their respective light-emitting panels, and a control circuit configured to control output currents of the DC/DC converters in accordance with illuminance data acquired with the photosensor. The control circuit successively turns on the plurality of light-emitting panels, and controls the output currents of the DC/DC converters in accordance with differences of the illuminance data acquired with the photosensor when the light-emitting panels are turned on. | 06-13-2013 |
20130162197 | METHOD FOR CHARGING LITHIUM ION SECONDARY BATTERY AND BATTERY CHARGER - A lithium ion secondary battery includes a positive electrode including a positive electrode active material layer containing lithium iron phosphate, a negative electrode including a negative electrode active material layer containing graphite, and an electrolyte including a lithium salt and a solvent including ethylene carbonate and diethyl carbonate between the positive electrode and the negative electrode. When the battery temperature of the lithium ion secondary battery or the temperature of an environment in which the lithium ion secondary battery is used is T and given temperatures are T | 06-27-2013 |
20130193434 | SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD THEREOF - An object is to reduce leakage current and parasitic capacitance of a transistor used for an LSI, a CPU, or a memory. A semiconductor integrated circuit such as an LSI, a CPU, or a memory is manufactured using a thin film transistor in which a channel formation region is formed using an oxide semiconductor which becomes an intrinsic or substantially intrinsic semiconductor by removing impurities which serve as electron donors (donors) from the oxide semiconductor and has larger energy gap than that of a silicon semiconductor. With use of a thin film transistor using a highly purified oxide semiconductor layer with sufficiently reduced hydrogen concentration, a semiconductor device with low power consumption due to leakage current can be realized. | 08-01-2013 |
20130193435 | SEMICONDUCTOR DEVICE - An object is to reduce leakage current and parasitic capacitance of a transistor used for an LSI, a CPU, or a memory. A semiconductor integrated circuit included in an LSI, a CPU, or a memory is manufactured using the transistor which is formed using an oxide semiconductor which is an intrinsic or substantially intrinsic semiconductor obtained by removal of impurities which serve as electron donors (donors) from the oxide semiconductor and has larger energy gap than a silicon semiconductor, and is formed over a semiconductor substrate. With the transistor which is formed over the semiconductor substrate and includes the highly purified oxide semiconductor layer with sufficiently reduced hydrogen concentration, a semiconductor device whose power consumption due to leakage current is low can be realized. | 08-01-2013 |
20130193874 | POWER SUPPLY CIRCUIT AND METHOD FOR DRIVING THE SAME - A power supply circuit with high power efficiency is provided. Alternatively, a power supply circuit with high power efficiency that is suitable for driving a light-emitting device is provided. The power supply circuit can switch current control in which driving is controlled based on information on current flowing through a load and voltage control in which driving is controlled based on information on voltage applied to a load. In a period during which voltage control is performed, a current detector for detecting current flowing through the load is deactivated so that current does not flow through the current detector. | 08-01-2013 |
20130257699 | DRIVER CIRCUIT, SIGNAL PROCESSING UNIT HAVING THE DRIVER CIRCUIT, METHOD FOR MANUFACTURING THE SIGNAL PROCESSING UNIT, AND DISPLAY DEVICE - Disclosed is a driver circuit including a latch circuit, a shift register circuit, and a switching circuit, where the latch circuit is provided over the shift register circuit and the switching circuit. The shift register circuit and the switching circuit may have a silicon-based semiconductor, while the latch circuit may have an oxide semiconductor. The latch circuit includes a first transistor and a second transistor connected in series. The latch circuit may further include a first capacitor and a second capacitor which are electrically connected to the first transistor and the second transistor. A display device using the driver circuit as well as a method for preparing the driver circuit is also disclosed. | 10-03-2013 |
20130261835 | POWER SUPPLY CONTROL DEVICE - An object is to reduce standby power in a data processing device, without loss of convenience, in a structure in which a power supply control device includes the data processing device. In a structure of a power supply control device which supplies power to an external device using a main switch, a data processing device is provided in the power supply control device to control the main switch; a sub-switch supplying power to the data processing device is provided; and a volatile memory unit and a nonvolatile memory unit are provided in the data processing device. Further, the sub-switch is off in a period in which data is stored in the nonvolatile memory unit of the data processing device, so that power supply to the data processing device is intermittently stopped. | 10-03-2013 |
20130265098 | SOLID-STATE RELAY - A solid-state relay is provided, which includes a first transistor, a second transistor, a first transmission circuit, and a second transmission circuit. A gate of the first transistor is connected to one of a source and a drain of the second transistor, one of a source and a drain of the first transistor is connected to a first terminal, and the other of the source and the drain of the first transistor is connected to a second terminal. The first transmission circuit supplies a first signal to the gate of the first transistor. The second transmission circuit supplies a second signal to a gate of the second transistor. The first terminal is connected to the second terminal when the first transistor is turned on by the first signal. | 10-10-2013 |
20130271220 | SEMICONDUCTOR DEVICE - Power consumption of a signal processing circuit is reduced. Further, power consumption of a semiconductor device including the signal processing circuit is reduced. The signal processing circuit includes a reference voltage generation circuit, a voltage divider circuit, an operational amplifier, a bias circuit for supplying bias current to the operational amplifier, and first and second holding circuits. The first holding circuit is connected between the reference voltage generation circuit and the bias circuit. The second holding circuit is connected between the voltage divider circuit and a non-inverting input terminal of the operational amplifier. Reference voltage from the reference voltage generation circuit and reference voltage from the voltage divider circuit can be held in the first and second holding circuits, respectively, so that the reference voltage generation circuit can stop operating. Thus, power consumption of the reference voltage generation circuit can be reduced. | 10-17-2013 |
20130293138 | CONTROL CIRCUIT HAVING SIGNAL PROCESSING CIRCUIT AND METHOD FOR DRIVING THE CONTROL CIRCUIT - 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. | 11-07-2013 |
20130314074 | MEASUREMENT DEVICE - To provide a measurement device which allows long-term accurate measurement of voltage without adversely affecting a device under test, by ensuring a predetermined level of resistance to ESD and reducing leakage current. A measurement device includes a probe needle for contacting a device under test, a first FET for detecting voltage of the device under test, and a protection circuit for protecting the first FET from static electricity. The protection circuit includes a second FET having an oxide semiconductor film as a channel formation region. | 11-28-2013 |
20140004393 | POWER STORAGE UNIT AND SOLAR POWER GENERATION UNIT | 01-02-2014 |
20140021904 | CHARGING DEVICE - A charging device used for charging a storage battery includes a first circuit that generates a current which depends on a charging current of the storage battery; a second circuit in which charge is accumulated by periodical supply of the current which depends on the charging current; and a third circuit that outputs a signal indicating completion of charge of the storage battery when the potential of the second circuit reaches a reference potential. The second circuit includes a capacitor and a transistor in which an oxide semiconductor is used for a channel formation region. The transistor is turned on or off in response to a pulse signal input to a gate of the transistor. The capacitor accumulates charge when the current depending on the charging current flows through the transistor. | 01-23-2014 |
20140162402 | SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD THEREOF - It is an object to provide a semiconductor device having a new productive semiconductor material and a new structure. The semiconductor device includes a first conductive layer over a substrate, a first insulating layer which covers the first conductive layer, an oxide semiconductor layer over the first insulating layer that overlaps with part of the first conductive layer and has a crystal region in a surface part, second and third conductive layers formed in contact with the oxide semiconductor layer, an insulating layer which covers the oxide semiconductor layer and the second and third conductive layers, and a fourth conductive layer over the insulating layer that overlaps with part of the oxide semiconductor layer. | 06-12-2014 |
20140176076 | POWER STORAGE DEVICE AND METHOD FOR CHARGING THE SAME - A decrease in the capacity of a power storage device is inhibited by adjusting or reducing imbalance in the amount of inserted and extracted carrier ions between positive and negative electrodes, which is caused by decomposition of an electrolyte solution of the negative electrode. Further, the capacity of the power storage device can be restored. Furthermore, impurities in the electrolyte solution can be decomposed with the use of the third electrode. A power storage device including positive and negative electrodes, an electrolyte, and a third electrode is provided. The third electrode has an adequate electrostatic capacitance. The third electrode can include a material with a large surface area. In addition, a method for charging the power storage device including the steps of performing charging by applying a current between the positive and negative electrodes, and performing additional applying a current between the third electrode and the negative electrode is provided. | 06-26-2014 |
20140184165 | POWER STORAGE DEVICE AND POWER STORAGE SYSTEM - 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. | 07-03-2014 |
20140184172 | POWER STORAGE DEVICE AND CHARGING METHOD THEREOF - 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. | 07-03-2014 |
20140184314 | SEMICONDUCTOR DEVICE - A coulomb counter is provided. In the coulomb counter, a current generated on charge or discharge of a secondary battery is converted into a voltage by a resistor, and the voltage is amplified by an amplifier circuit. The voltage amplified by the amplifier circuit is converted into a current by a voltage-current converter circuit, and the current is input to a cumulative addition circuit. The cumulative addition circuit charges a capacitor with the current input from the voltage-current converter circuit and generates a signal corresponding to a voltage generated across the capacitor. One terminal of the capacitor is connected to an output of the voltage-current converter circuit through a switch, and the other terminal of the capacitor is supplied with a constant potential. By on/off of the switch, supply of electric charge to the capacitor and storage of the electric charge can be controlled. | 07-03-2014 |
20140203654 | SECONDARY BATTERY, SECONDARY BATTERY MODULE, METHOD FOR CHARGING THE SECONDARY BATTERY AND THE SECONDARY BATTERY MODULE, METHOD FOR DISCHARGING THE SECONDARY BATTERY AND THE SECONDARY BATTERY MODULE, METHOD FOR OPERATING THE SECONDARY BATTERY AND THE SECONDARY BATTERY MODULE, POWER STORAGE SYSTEM, AND METHOD FOR OPERATING THE POWER STORAGE SYSTEM - 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. | 07-24-2014 |
20140266115 | VOLTAGE REGULATOR CIRCUIT - A voltage regulator circuit includes a transistor and a capacitor. The transistor includes a gate, a source, and a drain, a first signal is inputted to one of the source and the drain, a second signal which is a clock signal is inputted to the gate, an oxide semiconductor layer is used for a channel formation layer, and an off-state current is less than or equal to 10 aA/μm. The capacitor includes a first electrode and a second electrode, the first electrode is electrically connected to the other of the source and the drain of the transistor, and a high power source voltage and a low power source voltage are alternately applied to the second electrode. | 09-18-2014 |
20140266379 | SEMICONDUCTOR DEVICE - A sample-and-hold circuit including a transistor and a capacitor is connected to the differential circuit. The sample-and-hold circuit acquires voltage for correcting the offset voltage of the differential circuit by charging or discharging the capacitor through sampling operation. Then, it holds the potential of the capacitor through holding operation. In normal operation of the differential circuit, the output potential of the differential circuit is corrected by the potential held by the capacitor. The transistor in the sample-and-hold circuit is preferably a transistor whose channel is formed using an oxide semiconductor. An oxide semiconductor transistor has extremely low leakage current; thus, a change in the potential held in the capacitor of the sample-and-hold circuit can be minimized. | 09-18-2014 |
20140320107 | DC/DC Converter, Power Supply Circuit, And Semiconductor Device - Provided is a DC-DC converter with improved power conversion efficiency. A transistor which is incorporated in the DC-DC converter and functions as a switching element for controlling output power includes, in its channel formation region, a semiconductor material having a wide band gap and significantly small off current compared with silicon. The transistor further comprises a back gate electrode, in addition to a general gate electrode, and a back gate control circuit for controlling a potential applied to the back gate electrode in accordance with the output power from the DC-DC converter. The control of the potential applied to the back gate electrode by the back gate control circuit enables the threshold voltage to decrease the on-state resistance when the output power is high and to increase the off-state current when the output power is low. | 10-30-2014 |
20140333365 | SEMICONDUCTOR DEVICE - An object is to prevent malfunction of a power device. In a semiconductor device for driving a power device for power supply, a buffer circuit and a level-shift circuit are configured by transistors having the same conductivity type. Furthermore, a capacitor is provided in the level-shift circuit, and a signal to be boosted is supplied to the capacitor and is boosted using capacitive coupling of the capacitor. Furthermore, a structure can be employed in which the signal is boosted in such a manner that, in the level-shift circuit, a capacitor is provided between a wiring for supplying a low power source potential and a wiring for supplying a potential to boost the signal so that a power transistor can be driven. | 11-13-2014 |
20140367673 | SEMICONDUCTOR DEVICE - To provide a semiconductor device that holds data even when power supply is stopped. The semiconductor device includes a first transistor, a second transistor, a third transistor, and a capacitor. One of a source electrode and a drain electrode of the first transistor is electrically connected to one of a source electrode and a drain electrode of the third transistor and one electrode of the capacitor. A gate electrode of the second transistor is electrically connected to the other of the source electrode and the drain electrode of the third transistor. | 12-18-2014 |
20150028837 | DCDC CONVERTER - To provide a DCDC converter achieving low power consumption. A clock generation circuit, an error amplifier, a comparator, and a timer are included in a control circuit. The clock generation circuit, the error amplifier, and the comparator each include a bias circuit and a potential hold portion for intermittently holding a constant potential generated in the bias circuit. The potential hold portion includes a capacitor and a switch. The on or off of the switch is intermittently controlled using the timer. Even in a period in which the supply of voltage is stopped, a signal based on a constant potential generated in the bias circuit is continuously output. | 01-29-2015 |
20150034948 | SEMICONDUCTOR DEVICE - Electric charge is stored, in accordance with a bias voltage, in a gate of a transistor performing switching operation between an input terminal and an output terminal, and the gate is brought into an electrically floating state at the time of completing the storage of electric charge in the gate. One electrode of a capacitor is connected to the gate in an electrically floating state, and the potential of the other electrode of the capacitor is increased, so that the voltage of the gate is increased using capacitive coupling. The potential of the gate of the transistor is increased, and the bias voltage is sampled without being decreased. Each of the transistor performing switching operation and a transistor connected to the gate of the transistor is a transistor with an extremely low off-state current. | 02-05-2015 |
20150035509 | CONTROL CIRCUIT AND DC-DC CONVERTER - 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 2 | 02-05-2015 |
20150035514 | DC-DC CONVERTER AND SEMICONDUCTOR DEVICE - A DC-DC converter with low power consumption and high power conversion efficiency is provided. The DC-DC converter includes a first transistor and a control circuit. The control circuit includes an operational amplifier generating a signal that controls switching of the first transistor, a bias circuit generating a bias potential supplied to the operational amplifier, and a holding circuit holding the bias potential. The holding circuit includes a second transistor and a capacitor to which the bias potential is supplied. The first transistor and the second transistor include a first oxide semiconductor film and a second oxide semiconductor film, respectively. The first oxide semiconductor film and the second oxide semiconductor film each contain In, M (M is Ga, Y, Zr, La, Ce, or Nd), and Zn. The atomic ratio of In to M in the first oxide semiconductor film is higher than that in the second oxide semiconductor film. | 02-05-2015 |
20150035573 | SEMICONDUCTOR DEVICE - To increase the degree of integration of a semiconductor device such as a DCDC converter. In a semiconductor device (e.g., DCDC converter) including a controller circuit and a switching transistor, the switching transistor formed using an oxide semiconductor layer is stacked over a substrate on which the controller circuit is formed. The switching transistor includes a backgate to release heat generated in the oxide semiconductor layer. The backgate has electrical conduction with a wiring to release heat and prevent a temperature increase with integration. Moreover, for power saving, a potential hold portion including a transistor and a capacitor may be formed using part of the oxide semiconductor layer over the controller circuit. The potential hold portion is formed in a circuit for generating a bias potential in the controller circuit. | 02-05-2015 |