Abstract: Techniques disclosed herein cope with temperature effects in non-volatile memory systems. A control circuit is configured to sense a current temperature of the memory system and read, verify, program, and erase data in non-volatile memory cells by modifying one or more read/verify/program/erase parameters based on a temperature compensation value. The control circuit is further configured to read, verify, program, and erase data by accessing a historical temperature value stored in the memory system, the historical temperature value comprising a temperature at which a previous read, verify, program or erase occurred and measuring a current temperature value. The control circuit determines the temperature compensation value by applying a smoothing function.

Abstract: The memory device includes a plurality of memory cells arranged in a plurality of blocks, which are arranged in at least one plane. A controller is in electrical communication with the plurality of memory cells. The controller is configured to define a multi-block group that includes at least two blocks to be erased. The controller is further configured to simultaneously apply at least one erase pulse to the multi-block group. The controller is further configured to individually and sequentially apply a verify pulse to the blocks. In response to all blocks passing verify, the controller is configured to complete the erase operation. In response to at least one of the blocks not passing verify, the controller is configured to individually and sequentially apply an erase pulse and then a verify pulse to the at least one block that did not pass verify.

Abstract: The memory device includes a plurality of memory cell that arranged in an array, which includes a plurality of channels that are in electrical communication with a source line. The memory device also includes a controller that is configured to erase the memory cells in at least one erase pulse. During the at least one erase pulse, the controller is configured to drive the source line to an elevated voltage that is equal to an erase voltage Vera plus a kick voltage V_kick for a duration t_kick. The controller is then configured to reduce the voltage of the source line to the erase voltage Vera such that a voltage of the channel remains elevated during the entire erase pulse, including after the voltage of the source line has been reduced to the erase voltage Vera.

Abstract: A memory device that uses different programming parameters base on the word line(s) to be programmed is described. The programming parameter PROGSRC_PCH provides a pre-charge voltage to physical word lines. In some instances, the PROGSRC_PCH voltage is decoupled, and a new PROGSRC_PCH represents an adjusted (e.g., increased) pre-charge voltage for a certain physical word line or word line zone (i.e., predetermined group of word lines). Using different PROGSRC_PCH voltages can limit or prevent Vt distribution window degradation, particularly for relatively low physical word lines. Additionally, the overall programming time and average current consumed can also be reduced.

Abstract: Technology is disclosed herein for testing circuitry that controls memory operations in a memory structure having non-volatile memory cells. The testing of the circuitry can be performed without the memory structure. The memory structure may reside on one semiconductor die, with sense blocks and a control circuit on another semiconductor die. The control circuit is able to perform die level control of memory operations in the memory structure. The control circuit may control the sense blocks to simulate sensing of non-volatile memory cells in the memory structure even though the sense blocks are not connected to the memory structure. The control circuit verifies correct operation of the semiconductor die based on the simulated sensing. For example, the control circuit may verify correct operation of a state machine that controls sense operations at a die level. Thus, the operation of the semiconductor die may be tested without the memory structure.

Abstract: A method for programming a memory block of a non-volatile memory structure, comprising determining whether a number of programming/erase cycles previously applied to the block exceeds a first programming/erase cycle threshold and, if the first threshold is exceeded, determining whether the number of programming/erase cycles previously applied to the block exceeds an extended programming/erase cycle threshold. Further, if the determination is made that the extended threshold is not exceeded, the method comprises applying a two-pulse per programming loop scheme to each of the outermost strings of the block and applying a single-pulse per programming loop scheme to all other strings of the block. Alternatively, or in addition thereto, relative to a programming/erase cycle threshold, one or more outermost strings of the block may be unpermitted to be further programmed, and a “sub-block” comprised of all valid strings of the block may be defined and permitted for further programming.

Abstract: Technology is disclosed herein for efficient use of volatile memory that is used for accumulating parity data of user data being written to non-volatile memory cells. A memory controller may replace primary parity in a first portion of a parity buffer with data other than primary parity while a second portion of the buffer is still being used to store the primary parity. Therefore, the memory controller smartly re-uses the parity buffer, which makes efficient use of the volatile memory. In one aspect, a memory controller accumulates secondary parity for the user data in a first portion of the parity buffer while a second portion of the parity buffer is still being used to store the primary parity. The memory controller may compute the secondary parity from present content of the first portion of the parity buffer and primary parity presently stored in the second portion of the buffer.

Abstract: An apparatus includes control circuits configured to connect to a plurality of non-volatile memory cells. The control circuits are configured to abort fine programming of the plurality of non-volatile memory cells at an intermediate stage and read the plurality of non-volatile memory cells at the intermediate stage to obtain first partial data of at least one logical page. The control circuits are configured obtain the at least one logical page of data by combining the first partial data with second partial data of the at least one logical page stored in data latches.

Abstract: A memory apparatus and method of operation are provided. The memory apparatus includes memory cells connected to word lines and disposed in memory holes. The memory cells are connected in series between a drain-side select gate transistor on a drain-side and connected to one of a plurality of bit lines and a source line on a source-side. A control means is configured to apply a first and a second select gate voltage to the drain-side select gate transistor while applying a predetermined source line voltage to the source line of selected ones of the memory holes in a predetermined grouping and a read level voltage to at least one of the word lines associated with the predetermined grouping. The control means counts the memory cells conducting during each of a first and a second read operation and adjusts the predetermined source line voltage accordingly.

Abstract: A local data bus of a sense amplifier associated with one bit line is used to perform logical operations for a sensing operation performed by another sense amplifier associated with a different bit line. Each sense amplifier circuit includes a sensing node that is pre-charged, then discharged through a selected memory cell and a local data bus with a number of data latches connected. Target program data can be stored in the latches and combined in logical combinations with the sensed value of the memory cell to determine whether it has verified. By including a transfer circuit between the local data buses of a pair of sense amplifiers, the logical operations of a first sense amplifier can be performed using the local data bus of the paired sense amplifier, freeing the first sense amplifier's sense node to be concurrently pre-charged for a subsequent sensing operation, thereby improving performance.

Abstract: To help reduce program disturbs in non-selected NAND strings of a non-volatile memory, a sub-block based boosting scheme in introduced. For a three dimensional NAND memory structure, in which the memory cells above a joint region form an upper sub-block and memory cells below the joint region form a lower sub-block, dummy word lines in the joint region act as select gates to allow boosting at the sub-block level when the lower block is being programmed in a reverse order.

Abstract: Technology for limiting a voltage difference between two selected conductive lines in a cross-point array when using a forced current approach is disclosed. In one aspect, the selected word line voltage is clamped to a voltage limit while driving an access current through a region of the selected word line and through a region of the selected bit line. The access current flows through the memory cell to allow a sufficient voltage to successfully read or write the memory cell, while not placing undue stress on the memory cell. In some aspects, the maximum voltage that is permitted on the selected word line depends on the location of the selected memory cell in the cross-point memory array. This allows memory cells for which there is a larger IR drop to receive an adequate voltage, while not over-stressing memory cells for which there is a smaller IR drop.

Abstract: A memory apparatus and method of operation are provided. The memory apparatus includes memory cells connected to one of a plurality of word lines including an edge word line and a plurality of other data word lines. The memory cells are disposed in memory holes organized in rows grouped in a plurality of strings. The rows include full circle rows and semi-circle rows. A control means is configured to program the memory cells connected to the edge word line and in the semi-circle rows of a first one and a second one of the plurality of strings to a predetermined one of a plurality of data states in a first program operation. The control means then selects both the first one and the second one of the plurality of strings together and programs the memory cells of the full circle rows together in a second program operation.

Abstract: A memory device with adaptive sense time tables is disclosed. In order to maintain a desired (initial or preset) threshold voltage distribution, the sense time is adjusted as the program-erase cycle count increases. The program-erase cycle process tends to wear down memory cells, causing the QPW window to expand and the threshold voltage to widen. However, by adjusting (i.e., reducing) the sense time for increased program-erase cycles, the QPW window and the threshold voltage can be at least substantially maintained. Additionally, systems and methods for adjusting sense time based on die-to-die variations are also disclosed.

Abstract: A system has been described that performs differential temperature compensation based on a differential between the temperature at time of programming and temperature at time of reading for a set of data. Differential temperature compensation is useful for bulk programming/reading (e.g., many pages of data) and/or programming/reading super pages of data (multiple pages residing on different memory die).

Abstract: A method for performing a program verify operation with respect to a target memory cell in a memory structure of a non-volatile memory system, wherein the method may comprise determining a location of the target memory cell within the structure and, based upon the determined location of the target cell and with respect to each programmable memory state: (1) applying a first sense signal at a first point in time, and (2) applying a second sense signal at a second point in time, wherein a time interval between the first and the second points in time is equal to a predetermined optimal time period plus or minus an offset parameter time value.

Abstract: Technology for limiting a voltage difference between two selected conductive lines in a cross-point array when using a forced current approach is disclosed. In one aspect, the selected word line voltage is clamped to a voltage limit while driving an access current through a region of the selected word line and through a region of the selected bit line. The access current flows through the memory cell to allow a sufficient voltage to successfully read or write the memory cell, while not placing undue stress on the memory cell. In some aspects, the maximum voltage that is permitted on the selected word line depends on the location of the selected memory cell in the cross-point memory array. This allows memory cells for which there is a larger IR drop to receive an adequate voltage, while not over-stressing memory cells for which there is a smaller IR drop.

Abstract: A memory system identifies memory cells connected to a common word line that have had their threshold voltage unintentionally drift lower than programmed by determining whether memory cells meet two criteria: (1) the memory cells have threshold voltages within an offset of a read compare voltage of a data state; and (2) adjacent memory cells (connected to word lines that are adjacent to the common word line) are in one or more low data states. For those memory cells meeting the two criteria, the memory system performs some amount of programming on the memory cells to refresh the data stored in those memory cells to be as originally intended.

Abstract: The nonvolatile memory includes a plurality of nonvolatile memory cells configured to store multiple data states; a word line connected to a control gate of at least one of the plurality of non-volatile memory cells; a control gate line to supply a control gate signal; a word line switch connected between the word line and the control gate line to control the potential applied to the word line from the control gate line; and a memory controller circuit. The memory controller circuit is configured to control a word line potential on the word line and a control gate potential on the control gate line and to control a state of the control gate. The memory controller circuit, when the nonvolatile memory transitions to a not-on state, is further configured to turn off the word line switch and to charge the control gate line to a charged potential.

Abstract: A system has been described that performs differential temperature compensation based on a differential between the temperature at time of programming and temperature at time of reading for a set of data. Differential temperature compensation is useful for bulk programming/reading (e.g., many pages of data) and/or programming/reading super pages of data (multiple pages residing on different memory die).