Abstract:
A bootstrap circuit of which the capacitance of a bootstrap capacitor is small and which requires a shorter precharge period is provided. The bootstrap circuit includes transistors M41 and M42, capacitors BSC1 and BSC2, an inverter INV41, and keeper circuits 43 and 44. A signal OSG with a high voltage is generated from an input signal OSG_IN. As the signal OSG_IN is made a high level, a node SWG is made a high level by BSC1. After a signal BSE1 is made a high level and the node SWG is made a low level by the keeper circuit 44, a signal BSE2 is made a high level. By the capacitance coupling of BSC2, a voltage of an output terminal 22 increases.
Abstract:
A semiconductor device that can retain data for a long time is provided. The semiconductor device includes a first transistor and a second transistor. The first transistor contains an oxide semiconductor in a channel formation region. The second transistor includes a first gate and a second gate. A gate of the first transistor is connected to a first electrode of the first transistor. The first electrode of the first transistor is connected to the second gate. A negative potential is applied to a second electrode of the first transistor. The first electrode and the second electrode of the first transistor include a first end portion and a second end portion, respectively. The first end portion and the second end portion face each other. The first end portion includes a first arc and the second end portion includes a second arc when seen from the top. The radius of curvature of the second arc is larger than that of the first arc.
Abstract:
To provide a semiconductor device that is suitable for miniaturization. The semiconductor device includes a first transistor, a second transistor over the first transistor, a barrier layer between the first transistor and the second transistor, a first electrode between the first transistor and the barrier layer, and a second electrode between the hairier layer and the second transistor and overlapping the first electrode with the barrier layer therebetween. A gate electrode of the first transistor, the first electrode, one of a source electrode and a drain electrode of the second transistor are electrically connected to one another. A channel is formed in a first semiconductor layer including a single crystal semiconductor in the first transistor. A channel is formed in a second semiconductor layer including an oxide semiconductor in the second transistor.
Abstract:
To provide a small, highly reliable memory device with a large storage capacity. A semiconductor device includes a circuit for retaining data and a circuit for reading data. The circuit for retaining data includes a transistor and a capacitor. The circuit for reading data is configured to supply a potential to the circuit for retaining data and read a potential from the circuit for retaining data. The circuit for retaining data and the circuit for reading data are provided in different layers, so that the semiconductor device with a large storage capacity is manufactured.
Abstract:
An object is to miniaturize a semiconductor device. Another object is to reduce the area of a driver circuit of a semiconductor device including a memory cell. The semiconductor device includes an element formation layer provided with at least a first semiconductor element, a first wiring provided over the element formation layer, an interlayer film provided over the first wiring, and a second wiring overlapping with the first wiring with the interlayer film provided therebetween. The first wiring, the interlayer film, and the second wiring are included in a second semiconductor element. The first wiring and the second wiring are wirings to which the same potentials are supplied.
Abstract:
When a conductive layer occupying a large area is provided in a coiled antenna portion, it has been difficult to supply power stably. A memory circuit portion and a coiled antenna portion are disposed by being stacked together; therefore, it is possible to prevent a current from flowing through a conductive layer occupying a large area included in the memory circuit portion, and thus, power saving can be achieved. In addition, the memory circuit portion and the coiled antenna portion are disposed by being stacked together, and thus, it is possible to use a space efficiently. Therefore, downsizing can be realized.
Abstract:
To provide a microcontroller that can operate in a low power consumption mode. The microcontroller includes a CPU, a memory, and a peripheral circuit such as a timer circuit. A register of the peripheral circuit is formed at an interface with a bus line. A power gate is provided for control of power supply, and the microcontroller can operate in the low power consumption mode where some circuits alone are active, in addition to in a normal operation mode where all circuits are active. A register with no power supply in the low power consumption mode, such as a register of the CPU, includes a volatile memory and a nonvolatile memory.
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:
It is an object to provide a memory device where an area occupied by a memory cell is small, and moreover, a memory device where an area occupied by a memory cell is small and a data holding period is long. A memory device includes a bit line, a capacitor, a first insulating layer provided over the bit line and including a groove portion, a semiconductor layer, a second insulating layer in contact with the semiconductor layer, and a word line in contact with the second insulating layer. Part of the semiconductor layer is electrically connected to the bit line in a bottom portion of the groove portion, and another part of the semiconductor layer is electrically connected to one electrode of the capacitor in a top surface of the first insulating layer.
Abstract:
To read multilevel data from a memory cell having a transistor using silicon and a transistor using an oxide semiconductor, without switching a signal for reading the multilevel data in accordance with the number of the levels of the multilevel data. The electrical charge of a bit line is discharged, the potential of the bit line is charged via a transistor for writing data, and the potential of the bit line which is changed by the charging is read as multilevel data. With such a structure, the potential corresponding to data held in a gate of the transistor can be read by only one-time switching of a signal for reading data.