Abstract: A non-volatile semiconductor memory device comprises a memory cell array including a plurality of memory cells arrayed capable of storing information in accordance with variations in threshold voltage. A likelihood calculator has a plurality of likelihood calculation algorithms for deriving a likelihood value about a stored data bit from a threshold value read out of the memory cell. An error correction unit executes error correction through iterative processing using the likelihood value obtained at the likelihood calculator. A likelihood calculator controller changes among the likelihood calculation algorithms in the likelihood calculator based on a certain value of the number of iterations in the iterative processing obtained from the error correction unit.

Abstract: In a nonvolatile memory apparatus, a system bus receives address, command, and/or control signals. Memory cells store bits of data by shifting a threshold voltage to one of plural ranges. In writing a first page, the threshold voltage of a first memory cell remains in a first range or shifts into a second range. In writing a second page, the threshold voltage remains in the first or second voltages, or shifts into a third range from the first range or into a fourth range from the second range. Before writing the second page, the memory reads data from the first memory cell for generating the second page writing data. A shifting direction of the threshold voltage from the first to the second range is the same as a shifting direction from the first to the third range.

Abstract: A method of programming a nonvolatile memory device comprises selectively programming memory cells from a first state to a second state based on lower bit data, selectively programming the memory cells from the second state to an intermediate state corresponding to the lower bit data, and selectively programming the memory cells from the intermediate state to a third or fourth state based on upper bit data.

Abstract: First main bit lines correspond to at least one first memory cell. Second main bit lines correspond to at least one second memory cell. At least one sense amplifier outputs read data according to a difference between a voltage of any one of the first main bit lines and a voltage of any one of the second main bit lines. A voltage supply switching section supplies a predetermined reference voltage to one of the first main bit lines corresponding to one of the second main bit lines in which a current according to a threshold voltage of the at least one second memory cell is generated. A resistance switching section forms electrical connection between a ground node and the one of the second main bit lines in which the current according to the threshold voltage of the at least one second memory cell is generated with a predetermined resistance value.

Abstract: A method programs a nonvolatile memory device to program memory cells from one or more first logic states to two or more second logic states. In the method, a number of program voltages are provided to a selected word line, and verify voltages corresponding to the second logic states are provided to the selected word line. The number of the program voltages provided to the selected word line varies according to the threshold voltage difference between each of the first logic states and each of the second logic states.

Abstract: A method of performing an operation on a flash memory cell device, used when a gate coupling ratio between a floating gate and a control gate of less than 0.4. A potential is required to be applied across the control gate. Electrons are either injected to the floating gate from the control gate or ejected from the floating gate to the control gate. The operation associated with the injection or the ejection is determined by the nature of a silicon channel provided in the device. Devices using a bulk-tied FinFET-like structure are particularly suited to this method. The method is also particularly suited for use on cells in a NAND array.

Abstract: Provided is a method of operating a nonvolatile memory device to perform a programming operation or an erase operation. The method includes applying a composite pulse including a direct current (DC) pulse and an AC perturbation pulse to the nonvolatile memory device to perform the programming operation or the erase operation.

Abstract: There is provided a non-volatile memory which enables high accuracy threshold control in a writing operation. In the present invention, a drain voltage and a drain current of a memory transistor are controlled to carry out a writing operation of a hot electron injection system, which is wherein a charge injection speed does not depend on a threshold voltage. FIGS. 1A and 1B are views of a circuit structure for controlling the writing. In FIGS. 1A and 1B, an output of an operational amplifier 103 is connected to a control gate of a memory transistor 101, a constant current source 102 is connected to a drain electrode, and a source electrode is grounded. The constant current source 102 and a voltage Vpgm are respectively connected to two input terminals of the operational amplifier 103.

Abstract: An erasing method of post-programming in a nonvolatile memory device. The method includes post-programming dummy memory cells; verifying whether threshold voltages of the dummy memory cells are greater than or equal to a first voltage; post-programming normal memory cells; and verifying whether threshold voltages of the normal memory cells are greater than or equal to a second voltage. The first voltage is different from the second voltage.

Abstract: An apparatus, system, and method are disclosed for determining a read voltage threshold for solid-state storage media. A data set read module reads a data set from storage cells of solid-state storage media. The data set is originally stored in the storage cells with a known bias. A deviation module determines that a read bias for the data set deviates from the known bias. A direction module determines a direction of deviation for the data set. The direction of deviation is based on a difference between the read bias of the data set and the known bias. An adjustment module adjusts a read voltage threshold for the storage cells of the solid-state storage media based on the direction of deviation.

Abstract: In a non-volatile memory system, a programming speed-based slow down measure such as a raised bit line is applied to the faster-programming storage elements. A multi-phase programming operation which uses a back-and-forth word line order is performed in which programming speed data is stored in latches in one programming phase and read from the latches for use in a subsequent programming phase of a given word line. The faster and slower-programming storage elements can be distinguished by detecting when a number of storage elements reach a specified verify level, counting an additional number of program pulses which is set based on a natural threshold voltage distribution of the storage elements, and subsequently performing a read operation that separates the faster and slower programming storage elements. A drain-side select gate voltage can be adjusted in different programming phases to accommodate different bit line bias levels.

Abstract: Data storage circuits are connected to the bit lines in a one-to-one correspondence. A write circuit writes the data on a first page into a plurality of 5 first memory cells selected simultaneously by a word line. Thereafter, the write circuit writes the data on a second page into the plurality of first memory cell. Then, the write circuit writes the data on the first and second pages into second memory cells adjoining 10 the first memory cells in the bit line direction.

Abstract: Systems and methods for adjusting threshold voltage. A threshold voltage of a transistor of an integrated circuit is measured. A bias voltage, which when applied to a body well of the transistor corrects a difference between the threshold voltage and a desired threshold voltage for the transistor, is determined. The bias voltage is encoded into non-volatile storage on the integrated circuit. The non-volatile storage can be digital and/or analog.

Abstract: The invention provides an operation method of a memory system including a flash memory device. The method includes programming at least one page included in a selected memory block of the flash memory device; and determining the selected memory block or the flash memory device to be invalid, according to whether a loop number of the programmed page is out of a reference loop range.

Abstract: Memory devices and/or methods that may estimate characteristics of multi-bit cell are provided. A memory device may include: a multi-bit cell array; a monitoring unit to extract a threshold voltage change over time value for reference threshold voltage states selected from a plurality of threshold voltage states corresponding to data stored in the multi-bit cell array; and an estimation unit to estimate a threshold voltage change over time values for the plurality of threshold voltage states based on the extracted threshold voltage change. Through this, it is possible to monitor a change over time of threshold voltages of a memory cell.

Abstract: The present disclosure includes methods, devices, and systems for dealing with threshold voltage change in memory devices. A number of embodiments include an array of memory cells and control circuitry having sense circuitry coupled to the array. The control circuitry is configured to determine changes in threshold voltages (Vts) associated with the memory cells without using a reference cell, and adjust the sense circuitry based on the determined changes and without using a reference cell.

Abstract: A flash memory module and a method for programming a page of flash memory cells, the method includes: receiving a cycle count indication indicative of a number of program cycles of the page of memory cells; setting a value of a programming parameter of a programming operation based on the cycle count indication; and programming at least one flash memory cell of the page of flash memory cells by performing the programming operation.

Abstract: An array of programmable non-volatile devices use a floating gate that functions as a FET gate that overlaps a portion of a common source/drain region. This allows a programming voltage for the device to be imparted to the floating gate through capacitive coupling, thus changing the state of the device. The invention can be used in environments such as data encryption, reference trimming, manufacturing ID, security ID, and many other applications.

Abstract: A method and apparatus for a memory device is provided. The memory device includes a memory cell, a memory controller, and a temperature-sensing device that detects a temperature. The memory controller enables adjusting, based on the detected temperature, a parameter associated with a bit-altering operation to the memory cell that changes a threshold voltage of the memory cell such that the threshold voltage to which the memory cell is changed to by the bit-altering operation is compensated for variations in temperature.

Abstract: An erase method of a semiconductor device includes performing an operation comprised of supplying an erase pulse to erase the memory cells of a memory block, performing an erase verify operation for detecting memory cells of the memory block having threshold voltages dropped to a target erase voltage, from among the memory cells, performing a pre-program operation on the memory cells having the threshold voltages dropped to the target erase voltage, if, as a result of the erase verify operation, the memory block comprises memory cells having the threshold voltages higher than the target erase voltage and the memory cells having the threshold voltages dropped to the target erase voltage, and repeating the operation of supplying an erase pulse, the erase verify operation, and the pre-program operation until the threshold voltages of all the memory cells drop to the target erase voltage.

Abstract: In general, according to one embodiment, a nonvolatile semiconductor memory device includes: a memory cell array including memory cells; and a control unit to control a signal applied to the memory cells. Each of the memory cells are settable to: first, second and third states having first, second and third threshold voltage distributions (VD1, VD2 and VD3, VD1<VD3<VD2), respectively. In an operation of setting a second memory cell to the second state and setting a third memory cell to the third state, the control unit: sets the memory cells to the first state; sets the second memory cell to a state having a threshold voltage distribution between VD2 and VD3; performs a weak writing to increase a threshold voltage distribution of the memory cells; and sets the third memory cell to the third state.

Abstract: A programmable two terminal non-volatile device uses a floating gate that can be programed by a hot electron injection induced by a potential between a source and drain. The floating gate layer can also function as a FET gate for other circuits in an integrated circuit containing an array of the devices. The invention can be used in environments such as data encryption, reference trimming, manufacturing ID, security ID, and many other applications.

Abstract: An area saving electrically-erasable-programmable read-only memory (EEPROM) array, having: a plurality of parallel bit lines, a plurality of parallel word lines, and a plurality of parallel common source lines. The bit lines are classified into a plurality of bit line groups, containing a first group bit line and a second group bit line; the word line includes a first word line; and the common source lines include a first common source line. In addition, a plurality of sub-memory arrays are provided. Each sub-memory array contains a first, second, third, and fourth memory cells. Wherein, the first and second memory cells are symmetrically arranged, and the third and fourth memory cells are symmetrically arranged; also, the first and second memory cells, and the third and fourth memory cells are symmetrically arranged with the first common source line as a symmetric axis.

Abstract: A memory device and a method thereof allow programming and sensing a plurality of memory cells in parallel in order to minimize errors caused by coupling from fields of neighboring cells and to improve performance. The memory device and method have the plurality of memory cells linked by the same word line and a read/write circuit is coupled to each memory cells in a contiguous manner. Thus, a memory cell and its neighbors are programmed together and the field environment for each memory cell relative to its neighbors during programming and subsequent reading is less varying. This improves performance and reduces errors caused by coupling from fields of neighboring cells, as compared to conventional architectures and methods in which cells on even columns are programmed independently of cells in odd columns.

Abstract: A memory operating method includes the following steps. First, a memory with a charge storage structure is provided. Next, the memory is biased to a first threshold voltage. Then, the memory is biased to a second threshold voltage. Next, the memory is biased to a third threshold voltage. The first threshold voltage is higher than a first level. The second threshold voltage is lower than a second level. The third threshold voltage is approximating or equal to the second level.

Abstract: According to one embodiment, a nonvolatile semiconductor memory includes a control circuit. The control circuit is configured to repeat an application of a write pulse and a verify read operation to a selected word line, perform a read operation from a selected memory cell after storing of program data is judged to be completed by a verify circuit, and output a status information indicating that a program operation has passed to a external controller when data read by a read operation and a program data match and the status information indicating that the program operation has failed to the external controller when both do not match. A data latch circuit continues to latch the program data even after the storing of the program data is judged to be completed by the verify circuit.

Abstract: Memory devices and/or methods of storing memory data bits are provided. A memory device includes a multi-level cell (MLC) array including a plurality of MLCs, an error correction unit configured to encode data to be recorded in an MLC, where the encoded data is converted to convert the encoded data into a codeword, an error pattern analysis unit configured to analyze a first data pattern included in the codeword corresponding to an error pattern included in the codeword and a data conversion unit configured to convert the analyzed first data pattern into a second data pattern. According to the above memory devices and/or methods, it is possible to efficiently reduce a data error that occurs when the data is stored for a relatively long period of time, thereby improving reliability.

Abstract: A multi-dot flash memory set potentials of bit lines being disposed at a left side of a selected floating gate to V2(1)>V2(2)>V2(3)> . . . and set potentials of bit lines being disposed at a right side of the selected floating gate to V1(1)<V1(2)<V1(3)< . . . . Where V2(1) is a plus potential and V1(1) is a minus potential. The potentials of the bit lines converge on 0V with being away from the selected floating gate.

Abstract: A nonvolatile memory device has memory cells coupled to bit lines and word lines and page buffers each coupled to one or more of the bit lines. Program and verification operations are performed on a first logical page from among first and second logical pages included in memory cells selected for a program operation. Data are loaded which will be programmed into the second logical page into first to third latches of a selected page buffer, coupled to the selected memory cells, from among the page buffers. A data setting operation is performed. The second logical page is programmed so that a distribution of threshold voltages of the selected memory cells has one of first to fourth threshold voltage distributions according to states of the data of the first to third latches and performing verification operations for the first to fourth threshold voltage distributions.

Abstract: According to one embodiment, a nonvolatile semiconductor memory device includes a memory unit and a control unit. The memory unit includes a charge storage film and a memory cell transistor. The transistor is provided for each of storage regions configured to store charge in the film.

Abstract: Each of a plurality of flash memory cells is programmed to a respective one of L?2 threshold voltage states within a threshold voltage window. Values of parameters of threshold voltage functions are adjusted in accordance with comparisons of the threshold voltages of some or all of the cells to two or more of m?2 threshold voltage intervals within the threshold voltage window. Reference voltages for reading the cells are selected based on the values. Alternatively, the m threshold voltage intervals span the threshold voltage window, and respective threshold voltage states are assigned to the cells based on numbers of cells whose threshold voltages are in the intervals, without re-reading the cells.

Abstract: A method for erasing a non-volatile memory includes: performing a first pre-erase program step on the non-volatile memory; determining that the non-volatile memory failed to program correctly during the first pre-erase program step; performing a first soft program step on the non-volatile memory in response to determining that the non-volatile memory failed to program correctly; determining that the non-volatile memory soft programmed correctly; performing a second pre-erase program step on the non-volatile memory in response to determining that the non-volatile memory soft programmed correctly during the first soft program step; and performing an erase step on the non-volatile memory. The method may be performed using a non-volatile memory controller.

Abstract: A semiconductor memory device is described that can, in certain embodiments, reduce a delay in access time and/or an area of a memory cell array. In one or more embodiments, a flash memory device that includes a memory cell array, a data register, a state machine, input/output pads, a row decoder, and a column decoder. The memory cell array includes a pre-charge unit that is placed between a plurality of memory cell arrays. The pre-charge unit pre-charges a bit line in a read operation. A data register is separated from the pre-charge unit and is located away from the arrays. Write data are coupled from a data register to the arrays, and read data are coupled from the arrays to the data register.

Abstract: To program a set of non-volatile storage elements, a set of programming pulses are applied to the control gates (or other terminals) of the non-volatile storage elements. The programming pulses have pulse widths that vary as a function of simulated pulse magnitude data. The programming pulses can also have pulse magnitudes that vary based on measurements taken while testing the set of non-volatile storage elements. In one embodiment, the pulse widths are determined after simulation performed prior to fabrication of the non-volatile storage elements. In another embodiment, the pulse magnitudes are calculated after fabrication of the non-volatile storage elements.

Abstract: An electronic device can include a nonvolatile memory cell. In a particular embodiment, during an erase pulse, all unselected lines are at substantially the same voltage, and a row or segment of a row, such as a word, is erased during the erase pulse. In another embodiment, selected control gate and erase lines are at substantially the same voltage during a programming pulse. In a further embodiment, charge carriers tunnel through a dielectric layer of a component during a program pulse, and charge carriers tunnel through a different dielectric layer of a different component during an erase pulse.

Abstract: According to one embodiment, a semiconductor storage device includes a first cell, a second cell, a bit line, a first buffer, a second buffer, and a controller. The bit line transfers the data to the first cell and the second cell. The first buffer holds write data to the first cell and the second cell. The second buffer holds read data from the first cell. The controller controls first writing and rewriting executed for the first cell and second writing executed for the second cell. The write data in the first buffer is updated each time a second write signal is given. The controller executes the first writing based on the write data held by the first buffer. The controller performs the second writing based on the write data updated in the first buffer. The controller executes the rewriting based on the read data held by the second buffer.

Abstract: The structures and methods of reading out semiconductor Non-Volatile Memory (NVM) using referencing cells are disclosed. The new invented scheme can reduce large current consumption from the direct current biasing in the conventional scheme and achieve a high resolution on the cell threshold voltage with a good sensing speed.

Abstract: Threshold voltage distributions in a non-volatile memory device are narrowed, and/or programming time is reduced, using a programming technique in which the bit line voltage for storage elements having a target data state is stepped up, in lock step with a step up in the program voltage. The step up in the bit line voltage is performed at different times in the programming pass, for different subsets of storage elements, according to their target data state. The start and stop of the step up in the bit line voltage can be set based on a fixed program pulse number, or adaptive based on a programming progress. Variations include using a fixed bit line step, a varying bit line step, a data state-dependent bit line step, an option to not step up the bit line for one or more data states and an option to add an additional bit line bias.

Abstract: A nonvolatile semiconductor memory device is provided, which includes an input buffer provided with a first inverter that can electrically adjust circuit threshold values, a circuit: threshold value monitor provided with a second inverter having the same circuit configuration as the first inverter to detect the circuit threshold values of the first inverter when the input and output of the second inverter are short-circuited, respectively, a memory storing parameter values that correspond to the circuit threshold values detected by the circuit threshold value monitor, and a data-reader circuit reading the parameter values given to the first inverter from the memory.

Abstract: In various embodiments, the reference voltage used for read operations in a non-volatile memory may be adjusted up or down in an attempt to read data from an area that previously produced at least one uncorrectable error. The direction and amount of this adjustment may be based on the number and direction of correctable errors in surrounding data.

Abstract: Methods and memory devices configured to utilize predicted coupling effects of neighboring memory cells in the programming of target memory cells can be utilized to tighten the distribution of threshold voltages for a given bit pattern by compensating for anticipated threshold voltage shift due to capacitive coupling, which can facilitate more discernable Vt ranges, and thus a higher number of bits of data per memory cell. Tightening the distribution of threshold voltages can further facilitate wider margins between Vt ranges, and thus an increased reliability in reading the correct data value of a memory cell.

Abstract: The present invention includes methods, circuits and systems for reading non-volatile memory (“NVM”) cells, including multi-level NVM cells. According to some embodiments of the present invention, there may be provided a NVM cell threshold voltage detection circuit adapted to detect an approximate threshold voltage associated with a charge storage region of a NVM cell, where the NVM cell may be a single or a multi-charge storage region cell. A decoder circuit may be adapted to decode and/or indicate the logical state of a NVM cell charge storage region by mapping or converting a detected approximate threshold voltage of the charge storage region into a logical state value.

Abstract: Techniques are disclosed herein for erasing non-volatile memory cells. A subset of the memory cells are pre-conditioned prior to erase. The pre-conditioning alters the threshold voltage of the memory cells in a way that may help make later calculations more accurate. As an example, memory cells along a single word line might be pre-conditioned. After the pre-conditioning, the memory cells are erased using a trial erase pulse. A suitable magnitude for a second pulse is determined based on the magnitude of the trial erase pulse and data collected about the threshold voltage distribution after the trial erase. The second erase pulse is used to erase the memory cells. Determining an appropriate magnitude for the second erase pulse minimizes or eliminates over-erasing.

Abstract: In programming a selected word line of memory cells, a first program verify or read operation is performed, after one page of a selected word line is programmed, in order to determine a first quantity of memory cells that have been programmed to a predetermined reference point in the programmed first page distribution. Prior to programming the second page of the selected word line, a second program verify or read operation is performed to determine a second quantity of cells that are still at the reference point. The difference between the first and second quantities is an indication of the quantity of cells that experienced quick charge loss. The difference is used to determine an adjustment voltage for the second page verification operation after programming of the second page.

Abstract: A nonvolatile memory device includes a memory block including a number of cell strings, a channel voltage detection unit configured to detect channel voltages of the cell strings in which the channel voltages are changed based on voltages supplied to memory cells of the cell strings during a program operation and to generate channel voltage code based on an average channel voltage of the detected channel voltages, and a voltage supply unit configured to change a level of a pass voltage of the voltages supplied to memory cells in which the pass voltage is supplied to the memory cells during the program operation according to the channel voltage code.

Abstract: The present disclosure includes systems and techniques relating to non-volatile memory. A described device includes a non-volatile memory structure including a first data area, and a second data area that stores information. The information can include a first value corresponding to the first data area, the first value being set responsive to a last programming cycle on the first data area, and a second value indicating a total number of programming or erasing operations on the first data area.

Abstract: Multi-stage pulses are used to program/erase the memory so as to reduce the slow program/erase bit issue. A first predetermined voltage bias is applied to a memory cell for a predetermined number of times. Each time the voltage bias is applied to the memory cell the memory is verified against a criterion. If the verification failed after the predetermined number of times applying the first predetermined voltage bias, a second predetermined voltage bias is applied to program/erase the nonvolatile memory. If the verification failed after applying the second predetermined voltage bias, a third predetermined voltage bias is applied to program/erase the nonvolatile memory.

Abstract: A method for data storage includes storing first data bits in a set of multi-bit analog memory cells at a first time by programming the memory cells to assume respective first programming levels. Second data bits are stored in the set of memory cells at a second time that is later than the first time by programming the memory cells to assume respective second programming levels that depend on the first programming levels and on the second data bits. A storage strategy is selected responsively to a difference between the first and second times. The storage strategy is applied to at least one group of the data bits, selected from among the first data bits and the second data bits.

Abstract: A method for data storage includes storing multiple sets each including one or more read thresholds for use in reading data from a plurality of analog memory cells. The memory cells are arranged in multiple erasure blocks each including multiple pages, and each set of read thresholds is associated with a respective page in one of the erasure blocks. A first page, which belongs to a given erasure block and is not associated with any of the stored sets of read thresholds, is read by retrieving a stored set of read thresholds that is associated with a second page in the given erasure block, adapting the retrieved set of read thresholds to match the first page, and reading the first page using the adapted set of read thresholds.

Abstract: Various discussed approaches improve the over erase issue and the coupling effect, and include (A) multilevel contacts between (i) the first outer selected word line of an erase group, and (ii) the first unselected word line outside the ease group neighboring the first outer selected word line; (B) a sufficient separation distance between (i) the first outer selected word line of an erase group, and (ii) the first unselected word line outside the ease group neighboring the first outer selected word line. These are examples of electrically isolating (i) the first outer selected word line of an erase group, from (ii) the first unselected word line outside the ease group neighboring the first outer selected word line.