Abstract:
A semiconductor device including a nonvolatile memory cell in which a writing transistor which includes an oxide semiconductor, a reading transistor which includes a semiconductor material different from that of the writing transistor, and a capacitor are included is provided. Data is written to the memory cell by turning on the writing transistor and applying a potential to a node where a source electrode (or a drain electrode) of the writing transistor, one electrode of the capacitor, and a gate electrode of the reading transistor are electrically connected, and then turning off the writing transistor, so that the predetermined amount of charge is held in the node. Further, when a p-channel transistor is used as the reading transistor, a reading potential is a positive potential.
Abstract:
An imaging device capable of obtaining high-quality imaging data is provided. The imaging device includes a first circuit and a second circuit. The first circuit includes a photoelectric conversion element, a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a sixth transistor, a seventh transistor, a first capacitor, a second capacitor, and a third capacitor. The second circuit includes an eighth transistor. Variation in threshold voltage of an amplifier transistor (the fifth transistor) included in the first circuit can be compensated.
Abstract:
A semiconductor device with a novel structure in which stored data can be held even when power is not supplied and there is no limitation on the number of times of writing. In the semiconductor device, a plurality of memory cells each including a first transistor, a second transistor, and a capacitor is provided in matrix and a wiring (also called a bit line) for connecting one memory cell to another memory cell and a source or drain electrode of the first transistor are electrically connected to each other through a source or drain electrode of the second transistor. Accordingly, the number of wirings can be smaller than that in the case where the source or drain electrode of the first transistor and the source or drain electrode of the second transistor are connected to different wirings. Thus, the degree of integration of the semiconductor device can be increased.
Abstract:
A highly reliable semiconductor device. In a configuration where a precharged source line is discharged to a bit line by establishing electrical continuity between the source line and the bit line through a transistor to read a potential retained at a gate of the transistor, the potential of the bit line is switched in accordance with a change in potential of the source line due to the discharge. With this configuration, the voltage between the source and drain of the transistor can be kept lower than a predetermined voltage by discharge. Accordingly, the source-drain voltage of the transistor can be kept lower than its breakdown voltage, so that the semiconductor device can have high reliability.
Abstract:
A semiconductor device that inhibits deterioration of a secondary battery is provided. The semiconductor device includes a secondary battery module and a first circuit. The secondary battery module includes a secondary battery and a sensor. The first circuit includes a variable resistor. The sensor has a function of measuring a temperature of the secondary battery. The first circuit has a function of judging the charge voltage of the secondary battery and outputting a first result; a function of judging the temperature of the secondary battery measured by the sensor and outputting a second result; a function of determining the magnitude of the variable resistor on the basis of the first result and the second result; a function of discharging the charge voltage through the variable resistor; and a function of stopping discharge when the charge voltage reaches a specified voltage.
Abstract:
A semiconductor device using unipolar transistors, in which high and low levels are expressed using high and low power supply potentials, is provided. The semiconductor device includes four transistors, two capacitors, two wirings, two input terminals, and an output terminal. A source or a drain of the first transistor and a source or a drain of the fourth transistor are electrically connected to the first wiring. A gate of the fourth transistor is electrically connected to the first input terminal, and a gate of the second transistor is electrically connected to the second input terminal. A source or a drain of the second transistor and a source or a drain of the third transistor are electrically connected to the second wiring. The first transistor, the second transistor, and the two capacitors are electrically connected to the output terminal.
Abstract:
A memory device that can be highly integrated is provided. The memory device includes a first transistor and a second transistor in a memory cell, and small-area vertical transistors each including a channel formation region on a side surface of an opening portion provided in an insulating layer are used as the two transistors. The memory cell includes a conductor having a function of a gate electrode of the first transistor and a function of one of a source electrode and a drain electrode of the second transistor. The memory cells are placed in a staggered arrangement, so that the memory device can be highly integrated.
Abstract:
Provided is a power storage system, a secondary battery control system, a secondary battery measurement circuit, or the like that consumes low power. Provided is a power storage system, a secondary battery control system, a secondary battery measurement circuit, or the like that is highly integrated. The power storage system includes a secondary battery and a measurement circuit; the measurement circuit includes a resistor, a capacitor, and an inductor; one terminal of the resistor is electrically connected to one electrode of the capacitor; the other terminal of the resistor is electrically connected to one terminal of the inductor; one terminal of the inductor is electrically connected to a positive electrode of the secondary battery; and the measurement circuit has a function of measuring impedance of the secondary battery by measuring current of the resistor.
Abstract:
An imaging device with low power consumption is provided. A pixel includes a first circuit and a second circuit. The first circuit can generate imaging data and retain difference data that is a difference between the imaging data and data obtained in an initial frame. The second circuit includes a circuit that compares the difference data and a voltage range set arbitrarily. The second circuit supplies a reading signal based on the comparison result. With the use of the structure, reading from the pixel is not performed when it is determined that the difference data is within the set voltage range and reading from the pixel can be performed when it is determined that the difference data is outside the voltage range.
Abstract:
A small-sized and highly functional imaging device is provided. The imaging device includes a photoelectric conversion device formed on a silicon substrate and a transistor including a channel formation region in a silicon epitaxial growth layer formed on the silicon substrate. The transistor provided in the epitaxial growth layer has favorable electrical characteristics, so that the imaging device with little noise can be formed. Since the transistor can be formed so as to have a region overlapping with the photoelectric conversion device, the imaging device can be downsized.