Abstract: A non-volatile variable capacitive device includes a capacitor defined over a substrate, the capacitor having an upper electrode and a resistive memory cell having a first electrode, a second electrode, and a switching layer provided between the first and second electrodes. The resistive memory cell is configured to be placed in a plurality of resistive states according to an electrical signal received. The upper electrode of the capacitive device is coupled to the second electrode of the resistive memory cell. The resistive memory cell is a two-terminal device.

Abstract: A refresh leveraging driving method is provided which includes deciding a unit of word lines to be driven at a refresh leveraging operation to be the same as a redundancy repair row unit setting a lower row address of an input refresh leveraging address corresponding to the decided refresh leveraging row driving unit to a don't care state; and internally generating the don't care lower row address of the refresh leveraging address to drive word lines according to a combined refresh leveraging address.

Abstract: A novel semiconductor memory device whose power consumption is low is provided. A source of a writing transistor WTr_n_m, a gate of a reading transistor RTr_n_m, and one electrode of a capacitor CS_n_m are connected to each other. A gate and a drain of the writing transistor WTr_n_m are connected to a writing word line WWL_n and a writing bit line WBL_m, respectively. The other electrode of the capacitor CS_n_m is connected to a reading word line RWL_n. A drain of the reading transistor RTr_n_m is connected to a reading bit line RBL_m. Here, the potential of the reading bit line RBL_m is input to an inverting amplifier circuit such as a flip-flop circuit FF_m to be inverted by the inverting amplifier circuit. This inverted potential is output to the writing bit line WBL_m.

Abstract: A memory controller coupled to a memory chip having a number of sub-arrays of memory cells is configured to determine a configuration of the memory chip. The memory controller is configured to read the sub-array configuration of the memory chip and to detect sub-array level conflicts between external commands and refresh operations. The memory controller keeps one or more non-conflicting pages open during the refresh operations.

Abstract: A semiconductor device having a memory cell including a capacitor and a select transistor with a floating body structure, a bit line connected to the select transistor, a bit line control circuit, and a sense amplifier amplifying a signal read out from the memory cell. The bit line control circuit sets the bit line to a first potential during a non-access period of the memory cell, and thereafter sets the bit line to a second potential during an access period of the memory cell, so that the data retention time can be prolonged by reducing leak current at a data storage node of the memory cell so that an average consumption current for the data retention can be reduced.

Abstract: In a memory element including a pair of inverters, a capacitor which holds data, and a switching element which controls accumulating and releasing of electric charge of the capacitor are provided. For example, one electrode of the capacitor is connected to a first node, which is an input or output terminal of one of the pair of inverters, and the other electrode of the capacitor is connected to one electrode the switching element. The other electrode of the switching element is connected to a second node, which is the output or input terminal of the one of the pair of inverters. With such a connection structure, the absolute value of the potential difference between the first node and the second node at the time of data restoring can be large enough, whereby errors at the time of data restoring can be reduced.

Abstract: Provided is a multi-port cache memory apparatus and a method of the multi-port cache memory apparatus. The multi-port memory apparatus may divide an address space into address regions and allocate the divided memory regions to cache banks, thereby preventing the concentration of access to a particular cache.

Abstract: MIMCAP diodes are provided that can be suitable for memory device applications, such as current selector devices for cross point memory array. The MIMCAP diodes can have lower thermal budget as compared to Schottky diodes and controllable lower barrier height and lower series resistance as compared to MIMCAP tunneling diodes. The MIMCAP diode can include a barrier height modification layer, a low leakage dielectric layer and a high leakage dielectric layer. The layers can be sandwiched between two electrodes.

Abstract: It is an object to obtain a memory element (DRAM) storing multilevel data easily. The amount of charge accumulated in a capacitor of a memory element (DRAM) is controlled by changing the potential of a wiring (a bit line), which is used for writing data to the memory element (DRAM), in a period in which a transistor included in the memory element (DRAM) is on. Thus, multilevel data stored in the memory element (DRAM) can be obtained without a complex configuration of a semiconductor device including the memory element (DRAM).

Abstract: A memory includes a DRAM array having memory cells, wordlines and bitlines coupled to the memory cells, and sense amplifiers. The memory can be configured to perform a method in which a wordline of the DRAM array is set to an active state. While the wordline is active, signals develop on the respective bitlines according to the flows of charge between the memory cells coupled to the wordline and the respective bitlines. The sense amplifiers connected to the respective bitlines can remain inactive such that the sense amplifiers do not amplify the signals to storable signal levels. Then, when the wordline is set again to the inactive state, insufficient charge remains in the memory cells coupled to the wordline such that the data stored in memory cells coupled to the wordline are erased. These steps can be repeated using each of a remaining number of wordlines of all or a selected range of the DRAM array so as to erase the data stored in all of the DRAM array or a selected range.

Abstract: A programmable logic device includes a plurality of arithmetic circuits; a configuration changing circuit for changing a logic state of each of the plurality of arithmetic circuits by rewriting configuration data; a power supply control circuit for switching between start and stop of supply of power supply voltage to the plurality of arithmetic circuits; a state memory circuit for storing data on configuration, data on a state of power supply voltage, data on use frequency, and data on last use of each of the plurality of arithmetic circuits; and an arithmetic state control circuit for controlling the configuration changing circuit and the power supply control circuit in accordance with the data stored in the state memory circuit. One of the plurality of arithmetic circuits includes a transistor comprising an oxide semiconductor film in a channel formation region.

Abstract: An object is to increase the retention characteristics of a memory device formed using a semiconductor with a wide bandgap, such as an oxide semiconductor. A transistor including a back gate (a back gate transistor) is inserted in series at one end of a bit line so that the back gate is constantly at a sufficiently negative potential. The minimum potential of the bit line is set higher than that of a word line. When power is turned off, the bit line is cut off by the back gate transistor, ensuring prevention of outflow of charge accumulated in the bit line. At this time, the potential of a source or a drain (bit line) of a cell transistor is sufficiently higher than that of a gate of the cell transistor (0 V), so that the cell transistor is put in a sufficiently off state; thus, data can be retained.

Abstract: A memory interface device has an address input(s) configured to receive address information from an address stream of a host controller; an address output(s) configured to drive address information, and is coupled to a plurality of memory devices; an address match table comprising at least a revised address corresponding to a spare memory location; a control module configured to determine address information from an address stream from an address command bus coupled to a host controller during a run time operation; and a multiplexer coupled to the address input and coupled to the address output.

Abstract: A current memory cell includes an amplifier, transistor, first and second capacitors, and first to third switching units. The amplifier includes first to third terminals. The transistor is coupled to first and second nodes, and ground. The first capacitor is coupled between the second node and ground. The second capacitor is coupled between a third node and ground. The first unit couples a current source to the first node during a first period and an output line to the first node during a second period. The second unit couples the first node to the second node during the first period. The third unit couples the first terminal to the second node and couples the second and third terminals to the third node during the first period, and couples the first terminal to the third node and couples the second and third terminals to the second node during the second period.

Abstract: A semiconductor device may include a semiconductor substrate with first and second spaced apart source/drain regions defining a channel region therebetween and a control gate structure on the channel region between the first and second spaced apart source/drain regions. More particularly, the control gate structure may include a first gate electrode on the channel region adjacent the first source/drain region, and a second gate electrode on the channel region adjacent the second source/drain region. Moreover, the first and second gate electrodes may be electrically isolated. Related devices, structures, methods of operation, and methods of fabrication are also discussed.

Abstract: A reservoir capacitor includes a first capacitor group having two or more capacitors, which are serially coupled to each other between a first power voltage supply terminal and a second power voltage supply terminal, a second capacitor group having two or more capacitors, which are serially coupled to each other between a third power voltage supply terminal and a fourth power voltage supply terminal and a connection line suitable for electrically coupling a first coupling node between the capacitors of the first capacitor group to a second coupling node between the capacitors of the second capacitor group.

Abstract: Delays are introduced in self-timed memories by introducing a capacitance on the path of a signal to be delayed. The capacitances are realized by using idle-lying metal layers in the circuitry. The signal to be delayed is connected to the idle-lying capacitances via programmable switches. The amount of delay introduced depends on the capacitance introduced in the path of signal, which in turn depends on state of the switches. The state of the switches is controlled by delay codes provided externally to the delay introducing circuitry. Since idle-lying metal capacitances are utilized, the circuitry can be implemented using a minimum amount of additional hardware. Also, the delay provided by the circuitry is a function of memory cell SPICE characteristics and core parasitic capacitances.

Abstract: A memory device which can keep a stored logic state even when the power is off is provided. A signal processing circuit including the memory device, which achieves low power consumption by stopping supply of power, is provided. The memory device includes a logic circuit including a first node, a second node, a third node, and a fourth node; a first control circuit connected to the first node, the second node, and the third node; a second control circuit connected to the first node, the second node, and the fourth node; a first memory circuit connected to the first node, the first control circuit, and the second control circuit; and a second memory circuit connected to the second node, the first control circuit, and the second control circuit.

Abstract: A memory with extra digit lines in full size end arrays with an open digit architecture, which can use the extra digit lines to form repair cells. In one example, folded digit sense amplifiers are connected to an end array with an open digit architecture such that each sense amplifier corresponds to a group of four digit lines. Two digit lines of the group connect to two open digit sense amplifiers and the other two digit lines connect to the corresponding folded digit sense amplifier. A repair method can be performed on memories including the end arrays with folded digit sense amplifiers. A row in a core array including a replaceable IO is activated and a row in an end array is activated. The repair cells in the end array can be sensed by the folded digit sense amplifiers to generate a replacement IO, which is selected rather than the replaceable IO.

Abstract: In an embodiment of the invention, a method is provided for isolating a ferroelectric memory from a power supply during a write-back cycle or a write cycle of the ferroelectric memory. After it is determined that a write-back cycle or a write cycle will occur in the ferroelectric memory, the power supply is electrically disconnected from the ferroelectric memory before a write-back cycle or a write cycle occurs. Energy during the write-back cycle or the write cycle is provided to the ferroelectric memory by one or more capacitors in this embodiment. After the write-back cycle or the write cycle has ended, the power supply is electrically connected to the ferroelectric memory and the capacitors.

Abstract: A semiconductor memory device includes a memory cell array having a plurality of bit lines and a plurality of word lines intersecting each other and a plurality of nonvolatile memory cells; and a page buffer for each bit line including a latch configured to store one of data to be written to a first nonvolatile memory cell selected by each word line and data read from the first nonvolatile memory cell, wherein before reading out data, the page buffer configured to store in a replica capacitor a voltage value of a word line adjacent to the selected word line when a second nonvolatile memory cell is turned on, the replica capacitor including a first capacitor and a second capacitor connected in parallel, and the page buffer is configured to vary when the latch judges the data from the first nonvolatile memory cell according to the voltage value.

Abstract: A semiconductor memory device selects one of a plurality of memory cells as a dummy memory cell. The dummy memory cell is connected to a bit line that is complementary to a bit line connected to a selected memory cell. This technique advantageously compensates capacitance of the bit line. The semiconductor memory device comprises a selected memory cell connected to a first bit line and a first word line, a dummy memory cell connected to a second bit line complementary to the first bit line and a second word line, and a sense amplifier connected to the first and second bit lines and configured to read data stored in the selected memory cell by simultaneously enablement of the first and second word lines.

Abstract: A memory integrated circuit device is provided. The device includes a plurality of regular address inputs and at least one spare address input configured for a selected mode or an unselected mode. The device includes a plurality of control inputs, a plurality of data inputs, and a plurality of data outputs. The device has a plurality of memory arrays. Each of the memory arrays comprises a plurality of memory cells. Each of the plurality of memory cells is coupled to a data input/output. The device has a spare group of memory cells comprising a plurality of spare memory cells. Each of the plurality of spare memory cells is externally (or internally) addressable using the address match table and configured with the spare address input; whereupon the spare address input is coupled to the address match table to access the spare memory cells.

Abstract: An object is to increase the retention characteristics of a memory device formed using a wide bandgap semiconductor. A bit line controlling transistor is inserted in a bit line in series. The minimum potential of a gate of the transistor is set to a sufficiently negative value. The gate of the transistor is connected to a bit line controlling circuit connected to a battery. The minimum potential of the bit line is set higher than that of a word line. When power from an external power supply is interrupted, the bit line is cut off by the transistor, ensuring prevention of outflow of charge in the bit line. The potential of a source or a drain (bit line) of a cell transistor is sufficiently higher than that of a gate of the cell transistor, resulting in an absolute off-state; thus, data can be retained. Other embodiments are disclosed.

Abstract: A charge flow circuit for a time measurement, including a plurality of elementary capacitive elements electrically in series, each elementary capacitive element leaking through its dielectric space.

Abstract: In an exemplary aspect, the present invention provides a semiconductor memory device including sense amplifiers that drive bit lines to which memory cells are connected, and driver transistors that supply a power supply to the sense amplifiers, wherein the sense amplifiers are arranged in rows and constitutes a first sense-amplifier row in which transistors of a first conductive type are arranged and a second sense-amplifier row in which transistors of a second conductive type are arranged, and the driver transistors constitutes at least one transistor row including a first driver transistor of the first conductive type corresponding to the first sense-amplifier row and a second driver transistor of the second conductive type corresponding to the second sense-amplifier row between the first sense-amplifier row and the second sense-amplifier row.

Abstract: Apparatus and methods level shift a direct current (DC) component of a voltage rail signal from a first DC level to a second DC level such that voltage rail noise can be determined. The actual voltage rail noise can be compared to an expected amount of noise for analysis and validation of simulation models. Such assessment can be used to validate simulation models used to refine a design of an integrated circuit or as part of built-in self test.

Abstract: Embodiments of the disclosure provide a method for backing up data in an SRAM device, and an SRAM device that includes a capacitive backup circuit for backing up data in an SRAM device. The method may include writing data to the SRAM cell by applying an input voltage to set an input node of cross-coupled inverters to a memory state. The method may also include backing up the data written to the SRAM cell by electrically coupling the input node to the capacitive backup circuit. The method may also include restoring the data stored in the capacitive backup circuit to the SRAM cell by electrically coupling the capacitive backup circuit to the input node.

Abstract: A memory device includes a plurality of rows of memory cells, a refresh period determination unit, and a refresh control unit. The plurality of rows of memory cells includes a first row and one or more second rows. The refresh period determination unit is configured to set a refresh period according to read data from the first row. A refresh control unit is configured to control refreshing the one or more second rows based on the refresh period and to control obtaining the read data from the first row based on an adjustment interval.

Abstract: A multi-channel memory device includes a first channel memory and a second channel memory that are independently accessible within a same chip and that respectively include first and second power channel connection lines; a decoupling unit that can operationally connect or separate the first and second power channel connection lines in response to a decoupling driving signal; and a switching control unit that can apply the decoupling driving signal to the decoupling unit in response to a channel power control signal such that power supply voltages independently applied to the first and second channel memories are respectively used in corresponding first and second power channel connection lines.

Abstract: A memory device with low power consumption and a signal processing circuit including the memory device are provided. In a memory element including a phase-inversion element by which the phase of an input signal is inverted and the signal is output such as an inverter or a clocked inverter, a capacitor which holds data, and a switching element which controls storing and releasing of electric charge in the capacitor are provided. For example, one of electrodes of the capacitor is connected to an input terminal or an output terminal of the phase-inversion element, and the other electrode is connected to a switching element. The above memory element is used for a memory device such as a register or a cache memory in a signal processing circuit.

Abstract: A method and a memory for sensing a state of a memory cell while the memory cell capacitor is isolated from a data line are described. An activation device of the memory cell can be enabled to couple the memory cell capacitor to a parasitic capacitance of the active data line for charge sharing. The activation device can then be disabled to isolate the memory cell capacitor from the active data line. The state of the memory cell can then be sensed while the memory cell capacitor is isolated from the active data line. After the sense operation, the activation device can be re-enabled in order to restore the data to the memory cell capacitor that was destroyed during the sense operation.

Abstract: A memory device including first to fourth memory cell arrays and a driver circuit including a pair of bit line driver circuits and a pair of word line driver circuits is provided. The first to fourth memory cell arrays are overlap with the driver circuit. Each of the pair of bit line driver circuits and a plurality of bit lines are connected through connection points on an edge along the boundary between the first and second memory cell arrays or on an edge along the boundary between the third and fourth memory cell arrays. Each of the pair of word line driver circuits and a plurality of word lines are connected through second connection points on an edge along the boundary between the first and fourth memory cell arrays or on an edge along the boundary between the second and third memory cell arrays.

Abstract: To increase a storage capacity of a memory module per unit area, and to provide a memory module with low power consumption, a transistor formed using an oxide semiconductor film, a silicon carbide film, a gallium nitride film, or the like, which is highly purified and has a wide band gap of 2.5 eV or higher is used for a DRAM, so that a retention period of potentials in a capacitor can be extended. Further, a memory cell has n capacitors with different capacitances and the n capacitors are each connected to a corresponding one of n data lines, so that a variety of the storage capacitances can be obtained and multilevel data can be stored. The capacitors may be stacked for reducing the area of the memory cell.

Abstract: Some embodiments relate to a memory cell to store one or more bits of data. The memory cell includes a capacitor including first and second capacitor plates which are separated from one another by a dielectric. The first capacitor plate corresponds to a doped region disposed in a semiconductor substrate, and the second capacitor plate is a polysilicon or metal layer arranged over the doped region. The memory cell also includes a transistor laterally spaced apart from the capacitor and including a gate electrode arranged between first and second source/drain regions. An interconnect structure is disposed over the semiconductor substrate and couples the gate electrode of the transistor to the second capacitor plate.

Abstract: A memory device which can reduce power consumption and a driving method thereof are disclosed. In a memory element including an inverter and the like, a capacitor for holding data and a capacitor switching element for controlling store and release of charge in the capacitor are provided. The capacitor switching element is designed so that the off-state current is sufficiently low. Therefore, even when power supply of the inverter is stopped after charge corresponding to data is stored in the capacitor, data can be held for a long period of time. In order to return data, potentials of output and input terminals of the inverter are set to a precharge potential, then charge in the capacitor is released, and power is supplied to the inverter. A switching element for supplying the precharge potential may be provided.

Abstract: While the supply of power is stopped, a data signal that has been held in a volatile memory section can be held in a nonvolatile memory section. In the nonvolatile memory section, a transistor having an extremely low off-state current allows a data signal to be held in the capacitor for a long period of time. Thus, the nonvolatile memory section can hold the logic state even while the supply of power is stopped. When the supply of power is started again, the data signal that has been held in the capacitor while the supply of power has been stopped is set at such a potential that malfunction does not occur by turning on the reset circuit.

Abstract: A semiconductor device includes a first memory region including a plurality of memory cells; a test unit configured to test the first memory region, and detect a weak bit from among the plurality of memory cells; and a second memory region configured to store a weak bit address (WBA) of the first memory region, and data intended to be stored in the weak bit, wherein the first memory region and the second memory region include different types of memory cells.

Abstract: Providing for capacitive programming of two-terminal memory devices is described herein. By way of example, a capacitance circuit can be precharged to a predetermined program voltage to facilitate programming one or more memory cells. The capacitance circuit can be disconnected from a power source and connected instead to the memory cell(s), enabling charge stored by the capacitance circuit to discharge through the memory cell(s). A current at the memory cell(s) can program the cell, while a total amount of discharge is limited to the charge stored by the capacitance circuit. Limiting the total charge can serve to also limit joule heating of the target memory cell, power consumption of a memory device, as well as other benefits.

Abstract: A complementary metal-oxide-semiconductor (CMOS) dynamic random access memory (DRAM) cell with sense amplifier is described. In one embodiment, the DRAM cell includes an n-type field-effect transistor (NFET), a p-type field-effect transistor (PFET), and a storage capacitor accessed through both the NFET and the PFET. A pair of bit lines is coupled to the DRAM cell. A sense amplifier with a single-ended read path reads data in the DRAM cell through only one of the bit lines and a data-dependent write-back path writes back data to the DRAM cell through either one of the bit lines. The bit line used by the sense amplifier to write back the data to the DRAM cell depends on the logical value of the data.

Abstract: In a case where a DRAM and a ReRAM are mounted together, a manufacturing cost thereof is reduced while maintaining performance of a capacitance element and a variable resistance element. A semiconductor memory device includes a variable resistance element and a capacitance element. The variable resistance element has a cylinder type MIM structure with a first depth, and is designed for a variable resistance type memory. The capacitance element has a cylinder type MIM structure with a second depth deeper than the first depth, and is designed for a DRAM.

Abstract: A signal processing circuit including a nonvolatile storage circuit with a novel structure. The signal processing circuit includes a circuit that is supplied with a power supply voltage and has a first node to which a first high power supply potential is applied, and a nonvolatile storage circuit for holding a potential of the first node. The nonvolatile storage circuit includes a transistor whose channel is formed in an oxide semiconductor layer, and a second node that is brought into a floating state when the transistor is turned off. A second high power supply potential or a ground potential is input to a gate of the transistor. When the power supply voltage is not supplied, the ground potential is input to the gate of the transistor and the transistor is kept off. The second high power supply potential is higher than the first high power supply potential.

Abstract: A storage device in which held voltage is prevented from decreasing due to feedthrough in writing data to the storage device at high voltage is provided. The storage device includes a write circuit, a bit line, a word line, a transistor, and a capacitor. A gate of the transistor is electrically connected to the word line. One of a source and a drain of the transistor is electrically connected to the bit line. The other of the source and the drain of the transistor is electrically connected to one terminal of the capacitor. The other terminal of the capacitor is electrically connected to a ground. The write circuit includes an element holding write voltage and a circuit gradually decreasing voltage from the element holding write voltage. The write voltage is output from the write circuit to the word line.

Abstract: A semiconductor memory device is provided. A cell array includes a DRAM cell connected to one of a pair of bit lines. A bit line sense amplifier is coupled to the pair of bit lines. The bit line sense amplifier discharges a low-level bit line of the pair of bit lines toward a ground level and clamps the low-level bit line to a boosted sense ground voltage in response to a control signal. A sense amplifier control logic generates the control signal having a pulse interval. The low-level bit line is discharged toward the ground level for the pulse interval and after the pulse interval ends, the low-level bit line is clamped to the boosted sense ground voltage.

Abstract: A semiconductor memory device includes a bit line; two or more word lines; and a memory cell including two or more sub memory cells that each include a transistor and a capacitor. One of a source and a drain of the transistor is connected to the bit line, the other of the source and the drain of the transistor is connected to the capacitor, a gate of the transistor is connected to one of the word lines, and each of the sub memory cells has a different capacitance of the capacitor.

Abstract: A memory circuit includes a transistor having a channel in an oxide semiconductor layer, a capacitor, a first arithmetic circuit, a second arithmetic circuit, a third arithmetic circuit, and a switch. An output terminal of the first arithmetic circuit is electrically connected to an input terminal of the second arithmetic circuit. The input terminal of the second arithmetic circuit is electrically connected to an output terminal of the third arithmetic circuit via the switch. An output terminal of the second arithmetic circuit is electrically connected to an input terminal of the first arithmetic circuit. An input terminal of the first arithmetic circuit is electrically connected to one of a source and a drain of the transistor. The other of the source and the drain of the transistor is electrically connected to one of a pair of electrodes of the capacitor and to an input terminal of the third arithmetic circuit.

Abstract: A junctionless semiconductor device having a buried gate, a module and system each having the same, and a method for forming the semiconductor device are disclosed. A source, a drain, and a body of a semiconductor device having a buried gate are doped with the same type of impurities, so that the junctionless semiconductor device does not include a PN junction between the source and the body or between the body and the drain. As a result, a leakage current caused by GIDL is reduced so that operation characteristics of the semiconductor device are improved and the size of a current-flowing region is increased, resulting in an increased operation current.

Abstract: A phase change memory device includes: a memory cell arranged at a region where a word line and a bit line cross each other; and a control logic including: a program control logic configured to control a program operation of the memory cell; a read control logic configured to control a read operation of the memory cell; and an operation complete signal transfer unit configured to adjust a transfer time point of an operation complete signal transferred between the program control logic and the read control logic.

Abstract: In a conventional DRAM, when the capacitance of a capacitor is reduced, an error of reading data easily occurs. A plurality of cells are connected to one bit line MBL_m. Each cell includes a sub bit line SBL_n_m and 4 to 64 memory cells (a memory cell CL_n_m—1 or the like). Further, each cell includes selection transistors STr1_n_m and STr2_n_m and an amplifier circuit AMP_n_m that is a complementary inverter or the like is connected to the selection transistor STr2_n_m. Since parasitic capacitance of the sub bit line SBL_n_m is sufficiently small, potential change due to electric charge in a capacitor of each memory cell can be amplified by the amplifier circuit AMP_n_m without an error, and can be output to the bit line.

Abstract: A semiconductor memory device includes: a memory unit including a first memory sub region including a first memory cell and a second memory sub region including a second memory cell; a temperature information obtaining unit that obtains temperature information; a temperature estimation unit that estimates a first temperature of the first memory sub region and a second temperature of the second memory sub region based on the temperature information; a first sub region control unit that controls the first memory sub region based on the first temperature; and a second sub region control unit that controls the second memory sub region based on the second temperature.