Abstract: An SSD controller dynamically adjusts read thresholds in an NVM to reduce errors due to device threshold voltage distribution shifts, thus improving performance, reliability, and/or cost of a storage sub-system, such as an SSD. In a first aspect, the controller periodically performs offline tracking on a portion of the NVM. The controller reads a representative sub-portion with current read thresholds. If the read meets a condition, then the controller reads the sub-portion with sample read thresholds, estimates the device threshold voltage distributions, and adjusts the current read thresholds of the portion to calculated new operating read thresholds of the sub-portion. In a second aspect, the portion includes data with a known statistical average number of zero and/or one bits.

Abstract: The timing of logic read operations in a Flash memory device may be improved by a pad serial output circuit which receives a pre-decoded instruction signal and pre-fetched logic data prior to the last command clock, and which performs a fast resolution of the command in the pad serial output circuit on the last clock of the command input sequence. In one illustratively implementation, instruction pre-decode and data pre-fetch may be done on the seventh clock during command input. In another illustrative implementation, a first instruction pre-decode and data pre-fetch may be done on the fourth clock during command input, and a second instruction pre-decode may be done on the seventh clock during command input. Both serial protocol interface, including dual and quad I/O SPI, and quad peripheral interface are supported.

Abstract: A method for adaptive voltage range management in non-volatile memory is described. The method includes establishing an adaptive voltage range for a memory element of an electronic memory device. The memory element includes at least two states. The adaptive voltage range comprises a lower state and an upper state. The method also includes establishing an adjustment process to implement a first adjustment of an abode characteristic of a first state and to implement a second adjustment of an abode characteristic of a second state in the adaptive voltage range in response to a trigger event, wherein the first adjustment of an abode characteristic of the first state is different from the second adjustment of an abode characteristic of the second state.

Abstract: Methods and non-volatile storage systems are provided for using compensation that depends on the temperature at which the memory cells were programmed. Note that the read level compensation may have a component that is not dependent on the memory cells' Tco. That is, the component is not necessarily based on the temperature dependence of the Vth of the memory cells. The compensation may have a component that is dependent on the difference in width of individual Vth distributions of the different states across different temperatures of program verify. This compensation may be used for both verify and read, although a different amount of compensation may be used during read than during verify.

Abstract: A set of non-volatile storage elements are subjected to a programming process in order to store data. During the programming process, one or more verification operations are performed to determine whether the non-volatile storage elements have reached their target condition to store the appropriate data. Programming can be stopped when all non-volatile storage elements have reached their target level or when the number of non-volatile storage elements that have not reached their target level is less than a number or memory cells that can be corrected using an error correction process during a read operation (or other operation). The number of non-volatile storage elements that have not reached their target level can be estimated by counting the number of non-volatile storage elements that have not reached a condition that is different (e.g., lower) than the target level.

Abstract: A charge storage memory is configured in a NAND array, and includes NAND strings coupled to bit lines via string select switches and includes word lines. A controller is configured to produce a program bias pulse by biasing the bit lines and string select lines in a first condition; setting a word line coupled to a target cell to a first voltage level while the bit lines and string select lines are in the first condition; thereafter, biasing the bit lines and string select lines in a second condition; and setting the word line coupled to the target cell to a second voltage level higher than the first voltage level while the bit lines and string select lines are in the second condition. Program bias pulses produced in this manner can be used in a modulated incremental stepped pulse programming sequence.

Abstract: A nonvolatile memory device includes a memory cell array including a plurality of bitlines, a plurality of wordlines, and a plurality of memory cells. The memory device further includes a plurality of page buffers coupled to the respective bitlines of the memory cell array, each page buffer including a latch configured to store data to be written into and read from a memory cell coupled to a respective bitline of the memory cell array. The memory device further includes a control circuit configured to execute an over-program verify operation which includes detecting an over-programmed memory cell among the plurality of memory cells with reference to pass/fail data stored in the respective latches of the plurality of page buffers, and decreasing a threshold voltage of a detected over-programmed memory cell while maintaining a threshold voltage of memory cells which have not been detected as being over-programmed.

Abstract: According to one embodiment, a system includes a memory, a controller which controls an operation of the memory in a data program, and data bus which connects the memory to the controller. The memory comprises a memory cell array with memory cells which have a bit assignment to 2x (x is an integer number of 3 or more) threshold distributions, each memory cell storing x bits, and a control circuit which controls the data program of x bits to the memory cells. The controller comprises a first step generating y bit (y is an integer number and y<x) based on x bits, transferring y bit to the memory, and generating 2y threshold distributions based on y bit in the memory, and a second step executing after the first step, transferring x bits to the memory, and generating the 2x threshold distributions based on x bits in the memory.

Abstract: A semiconductor integrated circuit includes a memory cell area comprising a main cell and a spare cell, and a memory controller configured to set an offset value using a program verify level which is set during a program operation, and set a read level using the offset value during a read operation.

Abstract: According to one embodiment, a nonvolatile semiconductor memory device comprises a first memory cell, a second memory cell, and a control circuit. The first memory cell is connected to a first word line. The second memory cell is connected to a second word line which is adjacent to the first word line and has a width different from a width of the first word line. The control circuit applies a first voltage to the first word line and a second voltage different from the first voltage to the second word line. At least one of the first voltage and the second voltage is corrected by the control circuit based on write loop counts of the first memory cell and the second memory cell when the first memory cell and the second memory cell are write target cells in a write operation.

Abstract: A system, method and computer readable medium for performing a first read attempt of multiple codeword portions while using a first read threshold candidate to provide multiple first read results, wherein the multiple codeword portions are stored in multiple flash memory cells; calculating a first read threshold candidate error correction decoding based score; wherein the calculating comprises error correction decoding of the multiple first read results; performing a second read attempt of the multiple codeword portions while using a second read threshold candidate to provide multiple second read results; calculating a second read threshold candidate error correction decoding based score; wherein the calculating comprises error correction decoding of the multiple second read results; and selecting a first read threshold out of the first and second read threshold candidates based on a relationship between the first and second read threshold candidate error correction decoding based scores.

Abstract: A non-volatile semiconductor memory device includes an electrically data rewritable non-volatile semiconductor memory cell and a write circuit for writing data in the memory cell, the write circuit writing a data in the memory cells by supplying a write voltage Vpgm and a write control voltage VBL to the memory cell, continuing the writing of the data in the memory cell by changing the value of the write control voltage VBL in response to an advent of a first write state of the memory cell and inhibiting any operation of writing a data to the memory cell by further changing the value of the write control voltage VBL to Vdd in response to an advent of a second write state of the memory cell.

Abstract: According to one embodiment, a control unit multiple-selects a first line for every N lines from a plurality of first lines. N is an integer greater than or equal to one. The control unit sets the multiple-selected first lines to a selection potential, and fixes potentials of non-selected first lines at least adjacent to the multiple-selected first lines at a first timing. The control unit causes the multiple-selected first lines to be in a floating state at a second timing after the first timing. The control unit selects one second line from the plurality of second lines and sets the one second line to a forming potential at a third timing after the second timing.

Abstract: An integrated circuit memory is based on isolation device free memory cells. The memory cells are passively coupled to bit lines and word lines. The memory cells include an anti-fuse element and an element of phase change material in series. A rupture filament through the anti-fuse layer acts as an electrode for the phase change element. Control circuitry is configured to apply bias arrangements for operation of the memory cells, including a first write bias arrangement to induce a volume of the higher resistivity phase in the phase change material establishing a first threshold for the selected memory cell below a read threshold, a second write bias arrangement to induce a larger volume of the higher resistivity phase in phase change material establishing a second threshold for the selected memory cell above the read threshold, and a read bias arrangement to apply the read threshold to the selected memory cell.

Abstract: A method of operating a memory device comprises programming a first data signal to a first memory cell, attempting to program a second data signal to the first memory cell in a state where the first memory cell is not erased, and marking the first memory cell as blank upon failing to program the second data signal to the first memory cell.

Abstract: In a 3D stacked non-volatile memory device, the threshold voltages are evaluated and adjusted for select gate, drain (SGD) transistors at drain ends of strings of series-connected memory cells. To optimize and tighten the threshold voltage distribution, the SGD transistors are read at lower and upper levels of an acceptable range. SGD transistors having a low threshold voltage are subject to programming, and SGD transistors having a high threshold voltage are subject to erasing, to bring the threshold voltage into the acceptable range. The evaluation and adjustment can be repeated such as after a specified number of program-erase cycles of an associated sub-block. The condition for repeating the evaluation and adjustment can be customized for different groups of SGD transistors. Aspects include programming SGD transistors with verify and inhibit, erasing SGD transistors with verify and inhibit, and both of the above.

Abstract: A calibration module generates a plurality of calibration codes respectively for a first plurality of transistors located along (i) a plurality of bit lines and (ii) a first word line of a memory array. Each of the calibration codes is based on a distance of a corresponding one of the plurality of bit lines from an input of the first word line. A voltage generator outputs a first voltage generated based on a first plurality of codewords to an input of a second word line. A control module determines values of threshold voltages of a second plurality of transistors located along (i) the plurality of bit lines and (ii) the second word line based on (a) the first plurality of codewords and (b) currents sensed through the second plurality of transistors, and adjusts the values of the threshold voltages based on the calibration codes.

Abstract: A non-volatile semiconductor storage device according to an embodiment includes a memory cell array and a control circuit configured to execute a read operation. The control circuit refers to data of a reference memory cell which is adjacent to a selected memory cell and in which data is written after a data write operation on the selected memory cell. The control circuit applies a first read pass voltage to a non-selected word line adjacent to the selected word line, when the data of the reference memory cell is data causing the shift of the threshold voltage of the selected memory cell. The control circuit applies a second read pass voltage lower than the first read pass voltage to the non-selected word line, when the data of the reference memory cell is data not causing the shift of the threshold voltage of the selected memory cell.

Abstract: An instruction to perform an erase on a group of one or more memory cells is sent. An indication that the erasure of the group of memory cells is unsuccessful is received. In response to receiving the indication that the erasure of the group of memory cells is unsuccessful, the value of a voltage threshold, associated with the group of memory cells, is changed to a new voltage threshold and the new voltage threshold and identification information associated with the group of memory cells is stored.

Abstract: A non-volatile memory device is provided. The non-volatile memory device includes a cell string including a plurality of non-volatile memory cells; and an operation control block configured to supply a program voltage to a word line connected to a selected non-volatile memory cell among the plurality of non-volatile memory cells during a program operation, configured to supply a first negative voltage to the word line during a detrapping operation, and configured to supply a second negative voltage as a verify voltage to the word line during a program verify operation.

Abstract: A nonvolatile semiconductor memory device according to an embodiment includes a control circuit controlling a read operation of applying a read voltage to a selected memory cell to read data, and a write verify operation of applying a verify voltage to the selected memory cell. In a first case, the control circuit sets a voltage to a first write verify voltage and a first read voltage. In a second case in which the memory cells deteriorate more than in the first case, the control circuit sets a voltage to a second write verify voltage and a second read voltage. The control circuit sets a difference between a maximum value of the first write verify voltage and a maximum value of the first read voltage to be more than a difference between a maximum value of the second write verify voltage and a maximum value of the second read voltage.

Abstract: A semiconductor memory device includes memory cell blocks having physical pages coupled to memory cells, peripheral circuits configured to program the memory cells or read data stored in the memory cells, and a controller configured to control the peripheral circuits so that a pre-program is performed to make memory cells in the memory cell blocks have threshold voltages higher than a set voltage by programming memory cells of the selected memory cell block, having threshold voltages lower than the set voltage, in response to an erase command. The set voltage is an intermediate threshold voltage obtained from the threshold voltages of the memory cells of the selected memory cell block.

Abstract: An analog floating gate circuit (10-3, 10-4) includes a first sense transistor (21, 3), a first storage capacitor (20, 5), and first (24, 4) and second (31A, 42) tunneling regions. Various portions of a first floating gate conductor (12, 2) form a floating gate of the first sense transistor, a floating first plate of the first storage capacitor (20, 5), a floating first plate of the first tunneling region, and a floating first plate of the second tunneling region, respectively. A second plate of the first storage capacitor is coupled to a first reference voltage (VREF, GND), and a second plate of the second tunneling region is coupled to a second reference voltage (VPROG/GND). Compensation circuitry (44-1, 44-2) is coupled to the first floating gate conductor, for compensating loss of trapped charge from the first floating gate conductor.

Abstract: A program method of a nonvolatile memory device according to example embodiments includes a operation (a) of detecting a level of a program voltage; and a operation (b) of providing a unselected word line voltage and a bit line precharge voltage having a variable level respectively according to the detected level of the program voltage.

Abstract: A memory system having a plurality of memory cells for storing payload data and redundancy data. The memory system having a read-out circuit configured to read-out a status of the plurality of memory cells, the read-out status having payload data, redundancy data and associated reliability information. Moreover, the memory system has a data processor configured to derive the payload data from the read-out status using the reliability information.

Abstract: Provided is a method for reading data from a nonvolatile memory device. In the method, a read method includes a first read step including reading a first memory cell of the nonvolatile memory device by applying a first set of read voltages to the first memory cell. The read method further includes a second read step including reading the first memory cell by applying a second set of read voltages and none of the voltages in the first set to the first memory cell when it is determined that the first read step results in an error and cannot be corrected with error correction. The second read step is performed by using data resulting from the first read step.

Abstract: A semiconductor memory device according to an aspect of the present disclosure includes a first page buffer coupled to a first even bit line and a first odd bit line, a second page buffer coupled to a second even bit line and a second odd bit line, and a controller configured to control the first and the second page buffers so that the second page buffer sets the second even bit line in a floating state such that the voltage of the second even bit line is changed according to a shift in the voltage of the first odd bit line, when a read operation for memory cells coupled to the first odd bit line is performed, and the second page buffer stores data corresponding to the level of threshold voltages of the memory cells by detecting a shift in the voltage of the second even bit line.

Abstract: In writing, a first write operation to a first memory cell is executed; and a second write operation for providing a first threshold-voltage distribution to a second memory cell adjacent to the first one, is executed. The first threshold voltage distribution is a lowest threshold-voltage distribution among the positive threshold voltage distributions. It is verified whether a desired threshold voltage distribution has been obtained in the first memory cell or not (first write verify operation), moreover, it is verified whether a first threshold voltage distribution or a threshold voltage distribution having a voltage level larger than the first threshold-voltage distribution has been obtained in the second memory cell or not (second write verify operation). A control circuit outputs results of the first write verify operation and the second write verify operation.

Abstract: A programmable non-volatile configuration circuit uses a pair of non-volatile memory devices arranged in a pull-up and pull-down arrangement. The non-volatile memory devices have floating gates that overlaps a variable portion of a source/drain region. This allows a programming voltage for the device to be imparted to the floating gate through variable capacitive coupling, thus changing the state of the device. The invention can be used in environments to store configuration data for programmable logic devices, field programmable arrays, and many other applications.

Abstract: A storage unit for an occupant detection system detecting an occupant based on a magnitude correlation between a detection load value obtained by a load sensor and a threshold value, the storage unit includes a first ROM storing either one of the threshold value and a threshold value specific information for identifying the threshold value, the first ROM being rewritable and a second ROM storing information except for either one of the threshold value and the threshold value specific information, a rewriting of the second ROM being more difficult than a rewriting of the first ROM.

Abstract: A semiconductor integrated circuit has a central processing unit and a rewritable nonvolatile memory area disposed in an address space of the central processing unit. The nonvolatile memory area has a first nonvolatile memory area and a second nonvolatile memory area, which memorize information depending on the difference of threshold voltages. The first nonvolatile memory area has a maximum variation width of a threshold voltage for memorizing an information set larger than that of the second nonvolatile memory area. The first nonvolatile memory area can be prioritized to expedite a read speed of the memory information, and the second nonvolatile memory area can be prioritized to guarantee the number of times of rewrite operation of memory information.

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 nonvolatile random access memory that can be mounted on a substrate during a standard CMOS process. A memory cell comprises: a first MIS transistor including a first semiconductor layer of a first conductivity type in an electrically floating state, first drain and source regions of a second conductivity type formed on the first semiconductor layer, and a first gate electrode formed over the first semiconductor layer via a first gate insulating film; and a second MIS transistor including a second semiconductor layer of the first conductivity type isolated from the first semiconductor layer, second drain and source regions of the second conductivity type formed on the second semiconductor layer, a second gate electrode formed over the second semiconductor layer via a second gate insulating film. The first and second gate electrodes are electrically connected to each other so as to form a floating gate in an electrically floating state.

Abstract: The threshold voltages of particular nonvolatile memory cells on a word line are selectively increased on a column by column (cell by cell) basis. A selective program is performed on some of the cells, and simultaneously a program inhibit on other of the cells, resulting in all of the cells having a threshold voltage that falls between a minimum acceptable value and a maximum acceptable value.

Abstract: A bit line bias circuit of a memory architecture includes a varying voltage drop. In some embodiments, the voltage drop can depend on the threshold voltage of the memory cell selected to be read, or on the sense current flowing through the memory cell selected to be read.

Abstract: According to one embodiment, a one-time programmable (OTP) device comprises a memory FinFET in parallel with a sensing FinFET. The memory FinFET and the sensing FinFET share a common source region, a common drain region, and a common channel region. The memory FinFET is programmed by having a ruptured gate dielectric, resulting in the sensing FinFET having an altered threshold voltage and an altered drain current. A method for utilizing such an OTP device comprises applying a programming voltage for rupturing the gate dielectric of the memory FinFET thereby achieving a programmed state of the memory FinFET, and detecting by the sensing FinFET the altered threshold voltage and the altered drain current due to the programmed state of the memory FinFET.

Abstract: The switch transistors in the NAND strings have combinations of threshold voltage levels that vary across the levels of a three dimensional memory array. A bias arrangement is applied to the select lines electrically coupled to the switch transistors. The NAND strings on a particular level of a three dimensional memory array are selected. The NAND strings on other levels are deselected.

Abstract: The charge pump circuit has a plurality of cascaded charge pump stages, each provided with a first pump capacitor connected to a first internal node and receiving a first high voltage phase signal, and a second pump capacitor connected to a second internal node and receiving a second high voltage phase signal, complementary with respect to the first. A first transfer transistor is coupled between the first internal node and an intermediate node, and a second transfer transistor is coupled between the second internal node and the intermediate node. The first and second high voltage phase signals have a voltage dynamics higher than a maximum voltage sustainable by the first and second transfer transistors. A protection stage is set between the first internal node and second internal node and respectively, the first transfer transistor and second transfer transistor, for protecting the same transfer transistors from overvoltages.

Abstract: A method of programming a semiconductor memory device includes the steps of grouping memory cells in accordance with levels of threshold voltages to be programmed, programming the memory cell groups by sequentially applying program voltages to the memory cell groups, and program-verifying the memory cell groups.

Abstract: A method for operating a memory (28) includes storing data in a group of analog memory cells (32) of the memory as respective first voltage levels. After storing the data, second voltage levels are read from the respective analog memory cells. The second voltage levels are affected by cross-coupling interference causing the second voltage levels to differ from the respective first voltage levels. Cross-coupling coefficients, which quantify the cross-coupling interference among the analog memory cells, are estimated by processing the second voltage levels. The data stored in the group of analog memory cells is reconstructed from the read second voltage levels using the estimated cross-coupling coefficients.

Abstract: A method of reading a memory cell. The method includes the step of connecting (708) a reference voltage generator (600) to a first bitline (/BL). The first bitline is charged to a reference voltage (VREF) from the reference voltage generator. The reference voltage generator is disconnected (RFWL_A/B low at t4, FIG. 10B) from the first bitline. A signal voltage (PL high at t4, FIG. 10B) from the memory cell is applied to a second bitline (BL) after the step of disconnecting. A difference voltage between the first and second bitlines is amplified (SAEN high at t7, FIGS. 8A and 10B).

Abstract: According to one embodiment, a nonvolatile semiconductor memory device includes a memory cell array, write circuit, memory unit, and voltage generation unit. A plurality of strings is arranged in the memory cell array, each of which includes a plurality of memory cells connected to word lines. The write circuit selects a first string selected as a sample from the memory cell array, and writes data to the memory cell. The memory unit holds, for each word line, the number of write operations to each memory cell of the first string. When data is written to each memory cell of a second string other than the first string, the voltage generation unit generates an initial write voltage based on the number of write operations, which corresponds to the selected word line and is read out from the memory unit.

Abstract: Complementary Electrical Erasable Programmable Read Only Memory (CEEPROM) is disclosed. CEEPROM cell comprises a pair of non-volatile memory elements and one access transistor. The two elements of the non-volatile memory pair are configured to be one with high electrical conductance and the other with low electrical conductance. The positive voltage VDD for digital value “1” and ground voltage VSS for digital value “0” are connected to the two input nodes of the two non-volatile elements respectively after configuration. The digital signal either VDD or VSS passed through the high conductance non-volatile memory element in the pair is directly accessed by the access transistor without applying a sense amplifier as the conventional EEPROM would require. Without sense amplifiers, the digital data in CEEPROM can be fast accessed. The power consumption and the silicon areas required for sense amplifiers can be saved as well.

Abstract: Memory cells of a nonvolatile memory array are characterized by one of multiple threshold voltage ranges including at least an erased threshold voltage range and a programmed threshold voltage range. Responsive to an erase command to erase a group of memory cells of the nonvolatile memory array, a plurality of phases are performed, including at least a pre-program phase and an erase phase. The pre-program phase programs a first set of memory cells in the group having threshold voltages within the erased threshold voltage range, and does not program a second set of memory cells in the group having threshold voltages within the erased threshold voltage range in the group. By not programming the second set of memory cells, the pre-program phase is performed more quickly than if the second set of memory cells were programmed along with the first set of memory cells.

Abstract: A method for controlling a threshold value in a nonvolatile semiconductor memory device, includes: performing writing at least once on at least one of the memory cells to be adjusted to a state other than an erased state with an applied voltage that does not cause excess writing, with verify reading being not performed; and performing verify reading by applying a verify voltage corresponding to a target threshold value of the memory cell after the writing is performed on the at least one of the memory cells to be adjusted to the state other than the erased state, and, when the threshold value of the memory cell is determined to be lower than the target threshold value, repeating the writing with the applied voltage that does not cause excess writing and the verify reading until the threshold value of the memory cell becomes equal to or higher than the target threshold value.

Abstract: The present disclosure includes apparatuses and methods for determining soft data for combinations of memory cells. A number of embodiments include an array of memory cells including a first and a second memory cell each programmable to one of a number of program states, wherein a combination of the program states of the first and second memory cells corresponds to one of a number of data states, and a buffer and/or a controller coupled to the array and configured to determine soft data associated with the program states of the first and second memory cells and soft data associated with the data state that corresponds to the combination of the program states of the first and second memory cells based, at least in part, on the soft data associated with the program states of the first and second memory cells.

Abstract: A word line voltage generating method of a flash memory which includes generating a program voltage using a positive voltage generator; generating a plurality of negative program verification voltages corresponding to a plurality of negative data states using a negative voltage generator; and generating at least one or more program verification voltages corresponding to at least one or more states using the positive voltage generator. Generating a plurality of negative program verification voltages includes generating a first negative verification voltage; discharging an output of the negative voltage generator to become higher than the first negative verification voltage; and performing a negative charge pumping operation until an output of the negative voltage generator reaches a second negative verification voltage level.

Abstract: An error correction apparatus, a method thereof, and a memory device including the apparatus are provided. The error correction apparatus may include: a determination unit configured to determine whether a number of errors in a read word being read and extracted from a multi-level cell (MLC) exists in an error correcting capability range; a read voltage control unit configured to either increase or decrease a read voltage applied to the MLC when the number of errors in the read word is outside the error correcting capability range; and a codeword determination unit configured to analyze a bit error based on the increase or decrease of the read voltage, and to select a codeword corresponding to the analyzed bit error based on a selected read error pattern. Through this, it may be possible to efficiently correct a read error that occurs when the data of the memory device is maintained for a long time.

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: Provided is an erasing method of a nonvolatile memory device. The erasing method applies a word line erase voltage to a plurality of word lines connected to the memory cells respectively, applies a specific voltage to a ground selection line connected to the ground selection transistor, applies an erase voltage to a substrate in which the memory string formed during the step applying the specific voltage to the ground selection line, and floats the ground selection line in response to a voltage change of the substrate.