Abstract: According to one embodiment, a resistance change type memory includes: a variable resistance element connected between first and second bit lines; a write control circuit including first and second transistors with terminals connected to the first and second bit lines, respectively, and controlling write to the variable resistance element; a first interconnect supplied with a first voltage and connected to the first bit line via the first transistor; and a second interconnect supplied with a second voltage higher than the first voltage, and connected to the first bit line via the second transistor. The write control circuit supplies the second voltage to the first bit line with a first pulse width via the second transistor in the ON state after supplying the first voltage to the first bit line via the first transistor.

Abstract: A magnetic memory includes: a first and second terminals; a conductive layer including first to fourth regions, the first and fourth regions being electrically connected to the first and second terminals respectively; a first magnetoresistive element including: a first and second magnetic layers; a first nonmagnetic layer between the first and second magnetic layers; and a third terminal electrically connected to the first magnetic layer; a second magnetoresistive element including: a third and fourth magnetic layers; a second nonmagnetic layer between the third and fourth magnetic layers; and a fourth terminal electrically connected to the third magnetic layer; and a circuit configured to apply a write current between the first terminal and the second terminal and apply a first and second potentials to the third and fourth terminals respectively to write the first and second magnetoresistive elements, the first and second potentials being different from each other.

Abstract: According to one embodiment, a nonvolatile memory includes a conductive line including a first portion, a second portion and a third portion therebetween, a storage element including a first magnetic layer, a second magnetic layer and a nonmagnetic layer therebetween, and the first magnetic layer being connected to the third portion, and a circuit flowing a write current between the first and second portions, applying a first potential to the second magnetic layer, and blocking the write current flowing between the first and second portions after changing the second magnetic layer from the first potential to a second potential.

Abstract: According to one embodiment, a nonvolatile RAM includes a memory cell array, a first circuit being allowed to access the memory cell array in a write operation using a first pulse, and a second circuit being allowed to access the memory cell array in a read operation using a second pulse, the second circuit being allowed to operate in parallel with an operation of the first circuit. A width of the first pulse is longer than a width of the second pulse.

Abstract: A semiconductor storage device has a non-volatile memory, a memory controller to carry out write processing to the non-volatile memory using a write pulse, and a write pulse controller to select one of a first write mode for writing to the non-volatile memory and a second write mode for writing to the non-volatile memory with higher electric power consumption than the first write mode at higher speed than the first write mode and, when the first write mode is selected, set a pulse width of the write pulse such that the pulse width is shorter than one cycle of a clock signal used to control access to the non-volatile memory,

Abstract: According to one embodiment, a nonvolatile RAM includes a memory cell array, a first circuit being allowed to access the memory cell array in a write operation using a first pulse, and a second circuit being allowed to access the memory cell array in a read operation using a second pulse, the second circuit being allowed to operate in parallel with an operation of the first circuit. A width of the first pulse is longer than a width of the second pulse.

Abstract: A memory control circuit has a request determination circuitry to determine whether a period without read-out request and write request to an i-th (i being an integer of 1 or more and of n or less, n being an integer of 2 or more) level cache memory among first to n-th level cache memories continues for a first period of time or longer, the i-th level cache memory comprising a first nonvolatile memory, and a power-supply controller to control a power cut-off timing to the i-th level cache memory based on a determination of the request determination circuitry.

Abstract: According to an embodiment, a cache device includes a cache memory, an access controller, and a power controller. The cache memory includes a plurality of memory areas associated with a plurality of ways, respectively. The access controller controls access to the memory areas. The power controller controls power supplied to each of the memory areas individually such that power supplied to a memory area that has not been accessed for a predetermined time is standby power that is lower than operating power that enables the memory area to operate. The power controller controls power supplied to a memory area such that standby power for a memory area that is highly likely to be accessed has a value closer to the operating power than a value of standby power for a memory area that is less likely to be accessed.

Abstract: According to one embodiment, a magnetic random access memory includes a write circuit to write complementary data to first and second magnetoresistive elements, and a read circuit to read the complementary data from the first and second magnetoresistive elements. The control circuit is configured to change the first and second bit lines to a floating state after setting the first and second bit lines to a first potential, and change a potential of the first bit line in the floating state to a first value in accordance with a resistance value of the first magnetoresistive element and a potential of the second bit line in the floating state to a second value in accordance with a resistance value of the second magnetoresistive element by setting the common source line to a second potential higher than the first potential.

Abstract: A cache memory includes cache memory circuitry that is accessible per cache line and a redundant-code storage that stores one or more numbers of first redundant codes to be used for error correction of cache line data stored in the cache memory circuitry per cache line and one or more numbers of second redundant codes to be used for error detection of a part of the cache line data.

Abstract: A cache memory has cache memory circuitry comprising a nonvolatile memory cell to store at least a portion of a data which is stored or is to be stored in a lower-level memory than the cache memory circuitry, a first redundancy code storage comprising a nonvolatile memory cell capable of storing a redundancy code of the data stored in the cache memory circuitry, and a second redundancy code storage comprising a volatile memory cell capable of storing the redundancy code.

Abstract: A cache memory has a data cache to store data per cache line, a tag to store address information of the data to be stored in the data cache, a cache controller to determine whether an address by an access request of a processor meets the address information stored in the tag and to control access to the data cache and the tag, and a write period controller to control a period required for writing data in the data cache based on at least one of an occurrence frequency of read errors to data stored in the data cache and a degree of reduction in performance of the processor due to delay in reading the data stored in the data cache.

Abstract: According to one embodiment, a semiconductor device includes a processor chip, and a memory chip stacked on the processor chip with bumps and including a memory cell unit and a memory logic unit. The bumps are arranged on the memory logic unit. An address and data are transferred between the processor chip and the memory chip by use of shared bumps of the bumps.

Abstract: A magnetoresistive element according to an embodiment includes: a multilayer structure including a first magnetic layer, a second magnetic layer disposed above the first magnetic layer, and a nonmagnetic layer disposed between the first magnetic layer and the second magnetic layer; a conductor disposed above the second magnetic layer, and including a lower face, an upper face opposing to the lower face, and a side face that is different from the lower face and the upper face, an area of the lower face of the conductor being smaller than an area of the upper face of the conductor, and smaller than an area of an upper face of the second magnetic layer; and a carbon-containing layer disposed on the side face of the conductor.

Abstract: A semiconductor storage device has a non-volatile memory, a memory controller to carry out write processing to the non-volatile memory using a write pulse, and a write pulse controller to select one of a first write mode for writing to the non-volatile memory and a second write mode for writing to the non-volatile memory with higher electric power consumption than the first write mode at higher speed than the first write mode and, when the first write mode is selected, set a pulse width of the write pulse such that the pulse width is shorter than one cycle of a clock signal used to control access to the non-volatile memory,

Abstract: A memory control circuit has a request determination circuitry to determine whether a period without read-out request and write request to an i-th (i being an integer of 1 or more and of n or less, n being an integer of 2 or more) level cache memory among first to n-th level cache memories continues for a first period of time or longer, the i-th level cache memory comprising a first nonvolatile memory, and a power-supply controller to control a power cut-off timing to the i-th level cache memory based on a determination of the request determination circuitry.

Abstract: According to one embodiment, a magnetic random access memory includes a write circuit to write complementary data to first and second magnetoresistive elements, and a read circuit to read the complementary data from the first and second magnetoresistive elements. The control circuit is configured to change the first and second bit lines to a floating state after setting the first and second bit lines to a first potential, and change a potential of the first bit line in the floating state to a first value in accordance with a resistance value of the first magnetoresistive element and a potential of the second bit line in the floating state to a second value in accordance with a resistance value of the second magnetoresistive element by setting the common source line to a second potential higher than the first potential.

Abstract: According to one embodiment, a magnetic random access memory includes a write circuit to write complementary data to first and second magnetoresistive elements, and a read circuit to read the complementary data from the first and second magnetoresistive elements. The control circuit is configured to change the first and second bit lines to a floating state after setting the first and second bit lines to a first potential, and change a potential of the first bit line in the floating state to a first value in accordance with a resistance value of the first magnetoresistive element and a potential of the second bit line in the floating state to a second value in accordance with a resistance value of the second magnetoresistive element by setting the common source line to a second potential higher than the first potential.

Abstract: According to one embodiment, a random number generation circuit includes an oscillation circuit and a holding circuit. The oscillation circuit has an amplifier array and a high-noise circuit. Amplifiers are connected in series in the amplifier array, and the amplifier array has a terminal between neighboring amplifiers. The high-noise circuit is inserted between other neighboring amplifiers in the amplifier array, and the high-noise circuit generates noise required to generate jitter in an oscillation signal from the amplifier array. The holding circuit outputs, as a random number, the oscillation signal held according to a clock signal.

Abstract: According to one embodiment, a processor includes a core controlling processing data, a cache data area storing the processing data as cache data in a nonvolatile manner, a first tag area storing a tag data of the cache data in a volatile manner, a second tag area storing the tag data in a nonvolatile manner, a tag controller controlling the tag data. The tag controller determines whether the processing data is stored in the cache data area by acquiring the tag data from one of the first and second tag areas.