Abstract: A data storage device includes a nonvolatile memory device including a reference memory region and a normal memory region, and suitable for determining whether to perform a refresh operation, based on the reference memory region; and a controller suitable for determining a first memory region in the normal memory region based on wear leveling operation data, and controlling the nonvolatile memory device to perform the refresh operation for a second memory region excluding the first memory region in the normal memory region.

Abstract: A memory system includes a memory controller with multiple command/address ports and a memory device having corresponding request ports. The memory controller issues commands to memory device to cause the memory device to “loop-back” signals conveyed to memory device over one of the command/address ports via a bidirectional data link; these signals can be deterministic test patterns. The memory controller compares the returned information with the originally transmitted patterns to perform calibration. In one embodiment, because the return links are already calibrated, errors can be attributed to issues in the forward links; the memory controller then adjusts timing of the forward links to minimize the errors.

Abstract: Circuits and devices for bidirectional normally-off switches are described. A circuit for a bidirectional normally-off switch includes a depletion mode transistor and an enhancement mode transistor. The depletion mode transistor includes a first source/drain node, a second source/drain node, a first gate, and a second gate. The enhancement mode transistor includes a third source/drain node and a fourth source/drain node, and a third gate. The third source/drain node is coupled to the first source/drain node.

Abstract: High density capacitor structures based on an array of semiconductor nanorods are provided. The high density capacitor structure can be a plurality of capacitors in which each of the semiconductor nanorods serves as a bottom electrode for one of the plurality of capacitors, or a large-area metal-insulator-metal (MIM) capacitor in which the semiconductor nanorods serve as a support structure for a bottom electrode of the MIM capacitor subsequently formed.

Abstract: A volatile resistive memory device includes a resistive memory element including a barrier material portion and a charge-modulated resistive memory material portion. The barrier material portion includes a material selected from germanium and a silicon-germanium alloy, and the charge-modulated resistive memory material portion includes a non-filamentary, electrically conductive metal oxide. The resistive memory device may be a volatile eDRAM device. In operation, reading a resistance state of the resistive memory element does not disturb the resistance state of the charge-modulated resistive memory material portion.

Abstract: A memory device includes a memory cell array including a plurality of memory cells, a plurality of word lines connected to the plurality of memory cells, a plurality of bit lines connected to the plurality of memory cells, a plurality of complementary bit lines connected to the plurality of memory cells, a plurality of auxiliary bit lines, a plurality of auxiliary complementary bit lines, and a switch circuit. The switch circuit electrically connects the plurality of auxiliary bit lines to the plurality of bit lines during a write operation, electrically connects the plurality of auxiliary complementary bit lines to the plurality of complementary bit lines during the write operation, electrically disconnects the plurality of auxiliary bit lines from the plurality of bit lines during a read operation, and electrically disconnects the plurality of auxiliary complementary bit lines from the plurality of complementary bit lines during the read operation.

Abstract: A bit line architecture for dual-port static random-access memory (DP SRAM) is provided. An array of memory cells is arranged in rows and columns, and comprises a first subarray and a second subarray. A first pair of complementary bit lines (CBLs) extends along a column, from a first side of the array, and terminates between the first and second subarrays. A second pair of CBLs extends from the first side of the array, along the column, to a second side of the array. The CBLs of the second pair of CBLs have stepped profiles between the first and second subarrays. A third pair of CBLs and a fourth pair of CBLs extend along the column. The first and third pairs of CBLs electrically couple to memory cells in the first subarray, and the second and fourth pairs of CBLs electrically couple to memory cells in the second subarray.

Abstract: Described is an apparatus which comprises: a pass-gate; a sleep transistor configured as a diode-connected device controllable by the pass-gate; and a word-line driver coupled to the sleep transistor and the pass-gate.

Abstract: Memory cells including embedded SONOS based non-volatile memory (NVM) and MOS transistors are described. The memory cell includes a substrate having a non-volatile memory (NVM) region and a plurality of metal-oxide-semiconductor (MOS) regions. A NVM transistor in the NVM region includes a tunnel dielectric on the substrate, a charge-trapping layer on the tunnel dielectric, and a blocking dielectric comprising a high-k dielectric material over the charge-trapping layer. The plurality of MOS regions include a number of MOS transistors. At least one of the MOS transistors includes a gate dielectric comprising a high-k dielectric material over a surface of the substrate. Generally, the blocking dielectric and the gate dielectric comprise the same high-k dielectric material. Other embodiments are also described.

Abstract: The present invention relates to an improved sensing amplifier and related method for use in read operations in flash memory devices. In one embodiment, the sensing amplifier includes a built-in voltage offset. In another embodiment, a voltage offset is induced in the sensing amplifier through the use of capacitors. In another embodiment, the sensing amplifier utilizes sloped timing for the reference signal to increase the margin by which a “0” or “1” are detected from the current drawn by the selected cell compared to the reference cell. In an another embodiment, a sensing amplifier is used without any voltage offset.

Abstract: An extremely dense, high speed, and low power content addressable DRAM is presented. To enable a parallel searching, a data word to be searched may be driven onto column select lines (CSLs) of a DRAM array. Although two or more primary sense amplifiers typically are not connected at the same time to the same local data line during operation of a DRAM, in various embodiments presented herein, some or all sense amplifiers in a DRAM can be activated simultaneously to enable maximum parallelism with local data line sharing being explicitly allowed. Using this architecture, a data word can be simultaneously searched in all banks and with multiple wordlines. Since no input/output transactions are required and no data needs to be driven from the bank during execution of a search, overall current, and thus power usage, can be reduced.

Abstract: A multi-time programmable memory cell has a differential multi-time programmable memory cell and a second-level latch cell. The differential multi-time programmable memory cell provides a first balance signal and a second balance signal, and the second-level latch cell receives the first balance signal and the second balance signal and provides an output signal according to the first balance signal and the second balance signal based on a first latch control signal and a second latch control signal.

Abstract: A sense amplifier may be provided. The sense amplifier may include a first switch coupled between any one of a first signal line pair and a first power supply terminal. The sense amplifier may include a second switch coupled between the other one of the first signal line pair and the first power supply terminal. The sense amplifier may include a third switch configured to turn on the first switch depending on a level of the any one of the first signal line pair. The sense amplifier may include a fourth switch configured to turn on the second switch depending on a level of the other one of the first signal line pair.

Abstract: A memory device includes a nonvolatile memory unit, a volatile memory unit including first and second memory modules, and a controller configured to store data from the nonvolatile memory unit in the volatile memory unit before the data are transferred to a host. While the controller stores the data in the first memory module, the first memory module is in a first power state and the second memory module is in a second power state. The first power state corresponds to a high power consumption state and the second power state corresponds to a low power consumption state.

Abstract: A command sequence is restarted from the middle even when supply of power supply voltage to an internal circuit in a wireless tag is temporarily stopped (a power flicker occurs). A register or a cache memory included in a signal processing circuit in the wireless tag continues to retain data even after the supply of power supply voltage is stopped. After the power flicker occurs, the signal processing circuit in the wireless tag is returned to the state before the supply of power supply voltage is stopped and can restart signal processing. Consequently, the command sequence can be restarted from the middle.

Abstract: Memory cells including embedded SONOS based non-volatile memory (NVM) and MOS transistors are described. The memory cell includes a substrate having a non-volatile memory (NVM) region and a plurality of metal-oxide-semiconductor (MOS) regions. A NVM transistor in the NVM region includes a tunnel dielectric on the substrate, a charge-trapping layer on the tunnel dielectric, and a blocking dielectric comprising a high-k dielectric material over the charge-trapping layer. The plurality of MOS regions include a number of MOS transistors. At least one of the MOS transistors includes a gate dielectric comprising a high-k dielectric material over a surface of the substrate. Generally, the blocking dielectric and the gate dielectric comprise the same high-k dielectric material. Other embodiments are also described.

Abstract: A semiconductor device includes SRAM that stores data in an inverter loop including a CMOS inverter, transistors electrically connected to an input terminal or an output terminal of the CMOS inverter, and capacitors electrically connected to the corresponding transistors. The semiconductor device is configured to hold potentials corresponding to data at nodes between the transistors and the corresponding capacitors in a period during which supply of power to the CMOS inverter stops. In the period during which power supply stops, the potential of a wiring applying a low power supply potential is made equal to a high power supply potential to make the potentials of the input and output terminals of the CMOS inverter equal to the high power supply potential. The potentials corresponding to the data held at the nodes are applied to the input and output terminals of the CMOS inverter to restart power supply.

Abstract: A memory cell includes a node and first transistor to third transistors. The third transistor and the second transistor are electrically connected to a fourth wiring and a third wiring in series, respectively. A gate of the third transistor is electrically connected to a second wiring. A gate of the second transistor is electrically connected to the node. In the first transistor, a gate is electrically connected to a first wiring, one of a source and a drain is electrically connected to the fourth wiring, and the other of the source and the drain is electrically connected to the node. The first transistor includes an oxide semiconductor layer where a channel is formed and a channel length and a channel width thereof are each shorter than 100 nm. A maximum potential of the first wiring is lower than or equal to 2 V.

Abstract: A material belonging to the family of centrosymmetric Mott insulators is used as an active material in a resistively switched memory for storing data. The material is placed between two electrical electrodes, by virtue of which an electric field of a preset value is applied in order to form, by way of an electron avalanche effect, an elementary information cell that has at least two logic states.

Abstract: Methods for precharging bit lines using closed-loop feedback are described. In one embodiment, a sense amplifier may include a bit line precharge circuit for setting a bit line to a read voltage prior to sensing a memory cell connected to the bit line. The bit line precharge circuit may include a first transistor in a source-follower configuration with a first gate and a first source node electrically coupled to the bit line. By applying local feedback from the first source node to the first gate, the bit line settling time may be reduced. In some cases, a first voltage applied to the first gate may be determined based on a first current drawn from the first bit line. Thus, the first voltage applied to the first gate may vary over time depending on the conductivity of a selected memory cell connected to the bit line.

Abstract: Examples of the present disclosure provide apparatuses and methods related to performing comparison operations in a memory. An example apparatus might include a first group of memory cells coupled to a first access line and configured to store a first element. An example apparatus might also include a second group of memory cells coupled to a second access line and configured to store a second element. An example apparatus might also include sensing circuitry configured to compare the first element with the second element by performing a number of AND operations, OR operations, SHIFT operations, and INVERT operations without transferring data via an input/output (I/O) line.

Abstract: A semiconductor memory device may include a cell array comprising a plurality of memory cells, each memory cell connected to a word line and a bit line, the cell array divided into a plurality of blocks, each block including a plurality of word lines, the plurality of blocks including at least a first defective block; a nonvolatile storage circuit configured to store address information of the first defective block, and to output the address information to an external device; and a fuse circuit configured to cut off an activation of word lines of the first defective block.

Abstract: A refresh time detection circuit and a semiconductor device including the same may be provided. The refresh time detection circuit may include a code generator configured to generate a code signal for detecting a refresh time. The refresh time detection circuit may include a latch circuit configured to generate a latch signal by latching the code signal according to a fail signal, and generate a pre-code signal and a post-code signal by latching each latch signal according to a pre-enable signal and a post-enable signal. The refresh time detection circuit may include a subtractor configured to output a refresh detection signal by performing subtraction between the pre-code signal and the post-code signal. The refresh time detection circuit may include a comparator configured to generate a detection signal by comparing the refresh detection signal with an offset signal based on the post-enable signal.

Abstract: According to one embodiment, a storage device includes a memory, a controller, an interface unit, a switch, and a switch control unit. The memory stores data. The controller is configured to control writing of data to the memory and reading of data from the memory. The interface unit includes a first terminal, a second terminal, and a third terminal. The first terminal has an electrical status different between a case where the storage device and a first device are connected, and a case where the storage device and a second device are connected. Through the second terminal, voltage is applied by the first device to the storage device in the case where the storage device and the first device are connected, and a control signal is input from the second device to the storage device in the case where the storage device and the second device are connected. Through the third terminal, power is supplied to the storage device. The switch switches a connection status and a disconnection status.

Abstract: A ferroelectric static random access memory (FeSRAM) cell includes (a) first and second cross-coupled inverters connected between a power supply voltage signal and a ground reference voltage signal and holding a data signal represented in a complementary manner in first and second common data terminals; (b) first and second select transistors coupled respectively to the first and second common data terminals of the cross-coupled inverters; and (c) first, second, third and fourth ferroelectric capacitors, wherein the first and second ferroelectric capacitors couple the first common data terminal to the power supply voltage signal and the ground reference voltage signal, respectively, and wherein the third and the fourth ferroelectric capacitors couple the second common data terminal to the power supply voltage signal and the ground reference voltage signal, respectively.

Abstract: An integrated circuit (IC) package includes a storage element and a protection component coupled to the storage element. The protection component includes a breach detection component configured to detect an attempted breach of the IC package. The protection component further includes a time detection component configured to determine a breach timestamp associated with a time of occurrence of the attempted breach and configured to store a representation of the breach timestamp in the storage element. The storage element may be configured to store a sensitive datum, and the time detection component may be configured to store the representation of the breach timestamp by overwriting the sensitive datum in the storage element with the representation of the breach timestamp.

Abstract: Apparatuses are presented for a semiconductor device utilizing dual I/O line pairs. The apparatus includes a first I/O line pair coupled to a first local I/O line pair. A second I/O line pair may be provided coupled to a second local I/O line pair. The apparatus may further include a first bit line including at least a first memory cell and a second memory cell, and a second bit line including at least a third memory cell and a fourth memory cell may be provided. The first local I/O line pair may be coupled to at least one of the first and second bit lines, and the second local I/O line pair is coupled to at least one of the first and second bit lines.

Abstract: According to one embodiment, a semiconductor memory device includes a sense amplifier on a semiconductor substrate, a memory cell array including a memory cell above the sense amplifier, the memory cell including a capacitor and a first transistor, the capacitor including a first electrode and a second electrode, the first transistor including a first current path and a first control electrode controlling an on/off of the first current path, the first current path including a first terminal and a second terminal, the first terminal being electrically connected to the first electrode, and a first conductive line electrically connected to the second terminal and extending along an upper surface of the semiconductor substrate in a first direction, the first conductive line being electrically connected to the sense amplifier.

Abstract: A memory device with a novel structure that is suitable for a register file is provided. The memory device includes a first memory circuit and a second memory circuit. The first memory circuit includes a first logic element and a second logic element each of which is configured to perform logic inversion, a selection circuit, a first switch, a second switch, and a third switch. The second memory circuit includes a first transistor in which a channel formation region is provided in an oxide semiconductor film, a second transistor, and a capacitor to which a potential is supplied through the first transistor.

Abstract: Methods and apparatus for impedance adjustment operations in memory devices are disclosed. One such method includes adjusting an impedance of a particular driver circuit of a particular memory device to a desired impedance, determining configuration information corresponding to a configuration of the particular driver circuit adjusted to the desired impedance, transferring the configuration information to a different memory device and configuring an impedance of a driver circuit of the different memory device responsive to the configuration information.

Abstract: A semiconductor device with an improved arithmetic processing speed and a decreased circuit size, and its driving method are provided. In the semiconductor device, a first terminal of a first transistor and a gate of a second transistor are electrically connected to a first terminal of a capacitor, and a control circuit is electrically connected to a second terminal of the capacitor. The control circuit supplies a first potential to the second terminal of the capacitor, in other words, adds a value corresponding to the first potential to the value of first data previously retained in the gate of the second transistor in order to obtain second data. In the second transistor, the second data, specifically, a third potential commensurate with the potential of the gate will be output from a second terminal when a second potential is supplied to a first terminal.

Abstract: A novel semiconductor device, a semiconductor device capable of storing multi-level data, a semiconductor device with low power consumption, a semiconductor device with a reduced area, or a highly reliable semiconductor device is provided. The semiconductor device includes a memory cell which includes a first transistor and a capacitor, and a second transistor. The first transistor includes an oxide semiconductor in a channel formation region. One of a source and a drain of the first transistor is electrically connected to a first wiring. The other of the source and the drain of the first transistor is electrically connected to one of electrodes of the capacitor. The other of the electrodes of the capacitor is electrically connected to a second wiring. A gate of the second transistor is electrically connected to the first wiring.

Abstract: A semiconductor device which can write and read multilevel data is provided. A node connecting a source or a drain of an OS transistor and a gate of an OS transistor can hold the distribution of a plurality of potentials. A circuit configuration is employed in which the potential of the node is changed by capacitive coupling to control a conduction state of the OS transistor whose gate is connected thereto so that the potential of a gate of a Si transistor is changed. The potential of the gate of the Si transistor is changed positively in accordance with the potential change by capacitive coupling and is changed negatively in accordance with another transistor. In accordance with a change in value of current flowing through the Si transistor is detected, written data is read.

Abstract: A semiconductor device or a memory device with a reduced area, a large storage capacity, a high-speed operation, or low power consumption is provided. The semiconductor device includes a first transistor, a second transistor, a capacitor, a first wiring, a second wiring, a sense amplifier circuit, a decoder, a step-up circuit, a level shifter, and a buffer circuit. The first wiring is electrically connected to the buffer circuit and a second gate electrode of the first transistor. The second wiring is electrically connected to the sense amplifier circuit and the drain electrode of the second transistor. The capacitor is electrically connected to the drain electrode of the first transistor and the source electrode of the second transistor.

Abstract: A memory device with an array of memory cells, a write driver circuit, and a write assist circuit is disclosed. The write driver circuit and the write assist circuit can be located opposite to one another relative to the array of memory cells. The write assist circuit can compensate for a parasitic element in bitlines by transferring write voltages to addressed memory cells located in a portion of a memory array opposite to the write driver circuit. The parasitic element can be, for example, a bitline path resistance that causes a voltage differential between a voltage at the output of the write driver circuit and another voltage at a bitline location associated with the addressed memory cell. The write assist circuit can compensate for the voltage differential at the bitline location associated with the addressed memory cell; thus improving the performance of memory write operations.

Abstract: A memory system includes a control block, an antifuse voltage generator, an array voltage generator, and a memory array. The control block is used to output control signals to the memory array according to a memory control data signal. The antifuse voltage generator is used to output an antifuse control signal to the memory array according to a control signal and a driving voltage. The array voltage generator is used to output a selection signal and a following control signal to the memory array according a control signal. The memory array is coupled to the control block, the antifuse voltage generator, and the array voltage generator and configured to access data according to the first control signal, the antifuse control signal, the selection signal, and the following control signal. The first control signal comprises address information of the memory array.

Abstract: An object is to provide a memory device including a memory element that can be operated without problems by a thin film transistor with a low off-state current. Provided is a memory device in which a memory element including at least one thin film transistor that includes an oxide semiconductor layer is arranged as a matrix. The thin film transistor including an oxide semiconductor layer has a high field effect mobility and low off-state current, and thus can be operated favorably without problems. In addition, the power consumption can be reduced. Such a memory device is particularly effective in the case where the thin film transistor including an oxide semiconductor layer is provided in a pixel of a display device because the memory device and the pixel can be formed over one substrate.

Abstract: A voltage regulator includes a delay chain having a plurality of delay elements, a thermometer to binary encoder coupled to multiple nodes in the delay chain to provide a first binary number that is indicative of an estimated delay of the delay chain, and a latch coupled to the thermometer to binary encoder to receive the binary number. The voltage regulator also includes a signal processing circuit for providing a control signal indicative of a difference between the first binary number with a second binary number that represents a target delay, and a voltage control circuit coupled to the signal processing circuit for providing an output voltage based on the control signal from the processing circuit.

Abstract: According to one embodiment, a semiconductor memory device includes a first memory cell array including a first memory cell having a variable resistive element, a second memory cell array including a second memory cell having the variable resistive element, a reference signal generation circuit which generates a reference signal, a sense amplifier having a first input terminal and a second input terminal, and a read enable control circuit which generates a read enable signal in accordance with a command from outside and control switching between a single cell read mode and a twin cell read mode.

Abstract: A novel semiconductor device that can write and read multilevel data is provided. A memory cell includes a bit line, a power supply line, first and second nodes, first to fourth transistors, and first and second capacitors. One of two divided multilevel data is written to the first node through the first transistor. The other of the divided multilevel data is written to the second node through the second transistor. A gate of the third transistor is connected to the first node, and a gate of the fourth transistor is connected to the second node. The third and fourth transistors control electrical continuity between the bit line and the power supply line. Each of the first and second transistors preferably includes an oxide semiconductor in a semiconductor layer.

Abstract: A memory device capable of optimizing a refresh cycle is provided. The memory device includes a monitor circuit capable of generating a signal serving as a trigger for a refresh operation. The monitor circuit includes a transistor and a capacitor. The monitor circuit has a function of sensing that a potential retained in the capacitor is lower than a reference potential, a function of generating a first signal and a second signal on the basis of the sensing result, and a function of turning on the transistor in response to the second signal and resetting the potential retained in the capacitor to an initialization state. It is possible to start refresh of a memory cell in response to the first signal.

Abstract: An information processing apparatus according to an aspect of the present invention generates temperature distribution information (updated temperature information) that indicates the current temperature distribution in a memory chip, based on predetermined temperature information generated by an analysis executed in advance and temperature information obtained by a temperature sensor. The predetermined temperature information includes information related to the temperature distribution in the memory chip that corresponds to the operating states of an SoC die and a wide IO memory device. The information processing apparatus sets a thermal offset value to be used in the refresh operation of the memory chip, according to the difference between the temperature at the location of the temperature sensor and the temperature at a hotspot in the memory chip, which are included in the temperature distribution indicated by the updated temperature information.

Abstract: A semiconductor device that is suitable for miniaturization is provided. Alternatively, a highly reliable semiconductor device is provided. A semiconductor device including a capacitor and a transistor is provided. In the semiconductor device, the transistor includes a semiconductor layer, the semiconductor layer is positioned over the capacitor, and the capacitor includes a first electrode that is electrically connected to the transistor.

Abstract: A programmable read-only-memory (ROM) cell and method of operating. The ROM cell comprises: a silicon-on-insulator (SOI) substrate having a bottom substrate layer, an insulating layer formed over said bottom substrate layer, and a top semiconductor substrate layer. A series coupled CMOS NFET and PFET device is formed at said semiconductor substrate layer, each NFET and PFET device having a respective gate, drain and source terminals, wherein a source terminal of said PFET device is electrically shorted to a drain terminal of said NFET device. An injected charge storage layer is provided at an interface between a channel formed beneath a gate terminal of said PFET and the insulating layer. The charge storage layer having trapped charge carriers representative of a logic bit value. The stored bit value is physically undetectable data. Biasing conditions established at the substrate and PFET device enable injection of charge carriers into the charge storage layer.

Abstract: A method of operating a memory device includes writing cell data having one of at least three states to a memory cell; amplifying a voltage level of a bit line connected to the memory cell; determining that the cell data is in a first state when the voltage level of the bit line sensed at a sensing point is equal to or greater than a first reference voltage; determining that the cell data is in a second state when the voltage level of the bit line sensed at the sensing point is equal to or less than a second reference voltage which has a lower voltage level than the first reference voltage; and determining that the cell data is in a third state when the cell data is not in the first or second states.

Abstract: An IC may include an array of memory cells formed in a semiconductor, including memory cells arranged in rows and columns, each memory cell may include a floating body region defining at least a portion of a surface of the memory cell, the floating body region having a first conductivity type; a buried region located within the memory cell and located adjacent to the floating body region, wherein the buried region has a second conductivity type, wherein the floating body region is bounded on a first side by a first insulating region having a first thickness and on a second side by a second insulating region having a second thickness, and a gate region above the floating body region and the second insulating region and is insulated from the floating body region by an insulating layer; and control circuitry configured to provide electrical signals to said buried region.

Abstract: A semiconductor memory cell and arrays of memory cells are provided In at least one embodiment, a memory cell includes a substrate having a top surface, the substrate having a first conductivity type selected from a p-type conductivity type and an n-type conductivity type; a first region having a second conductivity type selected from the p-type and n-type conductivity types, the second conductivity type being different from the first conductivity type, the first region being formed in the substrate and exposed at the top surface; a second region having the second conductivity type, the second region being formed in the substrate, spaced apart from the first region and exposed at the top surface; a buried layer in the substrate below the first and second regions, spaced apart from the first and second regions and having the second conductivity type; a body region formed between the first and second regions and the buried layer, the body region having the first conductivity type; a gate positioned between the

Abstract: Techniques are described for examining data that may be communicated to a recipient in an item such as a gift certificate. In some cases, the data may include personal information, financial data, or otherwise sensitive data. To prevent inadvertent leakage of sensitive data to unauthorized processes or individuals, the sensitive data may be placed in a portion of memory that is accessible by authorized software modules. The modules may execute in a container that has access to the portion of memory. In some cases, a module may expose functions that are callable from outside the container. The functions may examine the data to determine whether portions of the data comply with requirements. The return values of the functions may indicate the results of the examination of the data without communicating the examined data.

Abstract: Provided is a memory device having a plurality of memory cells and a refresh circuit. Each of the memory cells is configured to retain multiple data as a potential of a node connected to a gate of a first transistor, one of a source and a drain of a second transistor, and one of electrodes of a capacitor. The refresh circuit is configured to refresh the memory cells. That is, the refresh circuit is configured to determine an interval between refresh operations, estimate a change of the potential of the node due to the leakage of the charge, and provide a refresh potential to the memory cells, where the refresh potential is a sum of the potential read from the node and the potential lost due to the charge leakage.

Abstract: A nonvolatile memory device includes a plurality of nonvolatile memory cells arranged in a substantially hexagonal pattern. The nonvolatile memory cells may be pillar shaped non-volatile memory cells which can be patterned using triple or quadruple exposure lithography or by using a self-assembling layer.