Abstract: A semiconductor device comprises a plurality of memory cells, a central processing unit, a timer circuit which times a RESET time, and a timer circuit which times a SET time. A threshold voltage of an NMOS transistor of each memory cell is lower than that of the peripheral circuit, thereby easily executing a RESET operation. The direction of a flowing current is changed across the RESET operation and the SET operation, and the bit lines are activated at high speed, thus preventing system malfunctions. Further, the semiconductor device can overcome such problems as a wrong write operation and data destruction, resulting from the variation in the CMOS transistors when operating phase change elements with minimum size CMOS transistors at a core voltage (e.g. 1.2 V). According to the present invention, stable operations can be realized at a low voltage, using minimum-size cell transistors.

Abstract: A semiconductor device includes a plurality of memory cells, and an error-correction circuit. Its write operation is performed by a late-write method, and ECC processing is executed in parallel with writing to shorten a cycle time. Moreover, when a memory cell is power-supplied through a well tap, the same address is not assigned while the memory cell is power-supplied through the well tap.

Abstract: There is provided semiconductor memory capable of reconfiguring an area to be given an authentication key and access limitation, and there is implemented an information distribution system having an advanced security function using the semiconductor memory. Part of a storage area in the semiconductor memory stores information about the area to be given the authentication key and the access limitation. Alternatively, the authentication key is stored in units of data to be authenticated for limiting an access to stored information. Information is protected doubly by storing encrypted information in the area provided with the access limitation according to the above-mentioned method.

Abstract: A semiconductor integrated circuit device is composed of logic gates each provided with at least two MOS transistors. The logic gates are connected to a first potential point and a second potential point. The semiconductor integrated circuit device includes a current control device connected between the logic gate and the first potential point and/or between the logic gate and the second potential point for controlling a value of a current flowing in the logic gate depending on an operating state of the logic gate. The circuit can be used in devices that cycle in operation between high and low power consumption modes, such as microprocessors that have both an operation mode and a low power back-up or sleep mode used for power reduction.

Abstract: A hybrid compressor includes a first compression mechanism, which is driven by a first drive source, and a second compression mechanism, which is driven by a second drive source, and a second radial axis of a second housing of the second compression mechanism is offset relative to a first radial axis of a first housing of the first compression mechanism, or a second diameter of the second housing of the second compression mechanism is less than a first diameter of the first housing of the first compression mechanism, or both. When a significant external force is applied to the front end of a vehicle containing the compressor, most of the external force may be absorbed by the first compression mechanism portion of the compressor, thereby reducing or avoiding damage to the second compression mechanism. In particular, when the second drive source is an incorporated electric motor, damage to the electric motor may be reduced or avoided.

Abstract: To improve the reliability of the phase change element, unwanted current should not be flown into the element. Therefore, an object of the present invention is to provide a memory cell that stores information depending on a change in its state caused by applied heat, as well as an input/output circuit, and to turn off the word line until the power supply circuit is activated. According to the present invention, unwanted current flow to the element can be prevented and thereby data destruction can be prevented.

Abstract: A magnetic memory device comprises a magnetic tunnel junction (MTJ) connecting to a bit line to a sense line through an isolation transistor. The MTJ includes a ferromagnetic layer having a magnetic hard axis. An assist current line overlies the bit line and is insulated from the bit line. The MTJ is switchable between a first, relatively high resistance state and a second, relatively low resistance state. The assist current line applies a magnetic field along the magnetic hard axis in the ferromagnetic layer, independently of current flow through the MTJ for assisting switching of the MTJ between the first and second states.

Abstract: A semiconductor device includes a plurality of memory cells, and an error-correction circuit. Its write operation is performed by a late-write method, and ECC processing is executed in parallel with writing to shorten a cycle time. Moreover, when a memory cell is power-supplied through a well tap, the same address is not assigned while the memory cell is power-supplied through the well tap.

Abstract: To improve the reliability of the phase change element, unwanted current should not be flown into the element. Therefore, an object of the present invention is to provide a memory cell that stores information depending on a change in its state caused by applied heat, as well as an input/output circuit, and to turn off the word line until the power supply circuit is activated. According to the present invention, unwanted current flow to the element can be prevented and thereby data destruction can be prevented.

Abstract: A semiconductor integrated circuit device is composed of logic gates each provided with at least two MOS transistors. The logic gates are connected to a first potential point and a second potential point. The semiconductor integrated circuit device includes a current control device connected between the logic gate and the first potential point and/or between the logic gate and the second potential point for controlling a value of a current flowing in the logic gate depending on an operating state of the logic gate. The circuit can be used in devices that cycle in operation between high and low power consumption modes, such as microprocessors that have both an operation mode and a low power back-up or sleep mode used for power reduction.

Abstract: In a memory using spin transfer torque, state of the spin is made unstable by applying a weak pulse before rewriting to reduce rewrite current. Reading of high-speed operation is performed with current in a regime where the current becomes non-linearly increases corresponding to the pulse width to suppress disturb. Further, fluctuation of respective memory cells is suppressed by a driving method setting the amount of spin constant by bit line charge to suppress read disturb.

Abstract: In MRAM using a spin-transfer torque switching, a sufficient writing operation with a small memory cell is realized, and a reading current is enlarged while a reading disturbance is suppressed. In the case where the free layer of the tunnel magneto-resistance element is located on the side of the bit line, using a PMOS transistor, and in the case where the fixed layer of the tunnel magneto-resistance element is located on the side of the bit line, using an NMOS transistor, an anti-parallel writing in a source grounding operation is performed. The reading and writing operation margin is improved by performing a reading operation in an anti-parallel writing direction.

Abstract: A magnetic memory device comprises a magnetic tunnel junction (MTJ) having a ferromagnetic free layer, and exhibits a first, relatively high resistance state, and a second, relatively low resistance state. To write to the magnetic memory device a current IMTJ is driven through the MTJ. For a first duration, the current is equal to a DC threshold current, being the DC current required to switch the multilayer structure between the first state and the second state. This induces a C-like domain structure in the free layer. For a second duration, the current IMTJ is larger than the DC threshold current. This causes the MTJ to switch states. The current requited to cause switching is less than that required using a uniform current pulse.

Abstract: Thresholds of MISFETS of a Full Depletion-type SOI substrate cannot be controlled by changing impurity density as with bulk silicon MISFETs. Therefore, it is difficult to set a suitable threshold for each circuit. According to the semiconductor device of the present invention, gate electrodes of P-channel type MISFETs composing a memory cell are made of N-type polysilicon, gate electrodes of N-channel type MISFETs are made of P-type polysilicon and gate electrodes of P-channel type and N-channel type MISFETs of peripheral circuits and a logic circuit are made of P-type silicon germanium. A suitable threshold can be achieved for each circuit using a SOI substrate, thereby making it possible to fully leverage the characteristics of the SOI substrate.

Abstract: A nonvolatile memory device of the present invention performs a programming operation by accumulating a charge in certain capacitance which is provided for each programming memory cell and injecting hot electrons generated when the charge is discharged via the memory cell into a floating gate. Thus, a variation in a programming characteristic of the nonvolatile semiconductor memory device is reduced, thereby realizing high-speed programming operation.

Abstract: A DRAM adopting a single-intersection memory cell array having randomly accessible data registers accessed whenever the chip is accessed externally. When data items recorded in the data registers are simultaneously written in the memory cell array, the data items are encoded. When data items are read from the memory cell array into the data registers, the data items are decoded. The margin is enhanced because array noise derived from reading is reduced. In addition, the access time of the DRAM is also reduced.

Abstract: A sense amplifier is constructed to reduce the occurrence of malfunctions in a memory read operation, and thus degraded chip yield, due to increased offset of the sense amplifier with further sealing down. The sense amplifier circuit is constructed with a plurality of pull-down circuits and a pull-up circuit, and a transistor in one of the plurality of pull-down circuits has a constant such as a channel length or a channel width larger than that of a transistor in another pull-down circuit. The pull-down circuit with a larger constant of a transistor is first activated, and then, the other pull-down circuit and the pull-up circuit are activated to perform the read operation.

Abstract: To enable one non-volatile memory cell to store four-value information, three different kinds of threshold voltages are serially applied to a word line in a verify operation to execute a write operation, the threshold voltages of the memory cell are controlled, and two-value (one-bit) information corresponding to the four-value (two-bit) information to be written are synthesized by a write data conversion circuit for each of the write operations carried out three times. In this way, the four-value (two-bit) information are written into one memory cell, and the memory capacity of the memory cell can be increased. In the information read operation, three different kinds of voltages are applied to a word line, three kinds of two-value (one-bit) information so read out are synthesized by a read conversion circuit and the memory information of the memory cell are converted to the two-bit information.

Abstract: A semiconductor device comprises a plurality of memory cells, a central processing unit, a timer circuit which times a RESET time, and a timer circuit which times a SET time. A threshold voltage of an NMOS transistor of each memory cell is lower than that of the peripheral circuit, thereby easily executing a RESET operation. The direction of a flowing current is changed across the RESET operation and the SET operation, and the bit lines are activated at high speed, thus preventing system malfunctions. Further, the semiconductor device can overcome such problems as a wrong write operation and data destruction, resulting from the variation in the CMOS transistors when operating phase change elements with minimum size CMOS transistors at a core voltage (e.g. 1.2 V). According to the present invention, stable operations can be realized at a low voltage, using minimum-size cell transistors.

Abstract: A CMOS circuit in low-voltage implementation, low power-consumption implementation, high-speed implementation, or small-size implementation. In a circuit which uses a FD-SOI MOST where a back gate is controlled by a well, voltage amplitude at the well is made larger than input-voltage amplitude at the gate. Alternatively, the circuit is modified into a circuit which uses a MOST that changes dynamically into an enhancement mode and a depletion mode.