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 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 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 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: 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 memory apparatus and method of operation are provided. The memory apparatus includes memory cells configured to retain a threshold voltage. The memory cells are connected to one of a plurality of word lines and are arranged in strings comprising a plurality of blocks. A control means is coupled to the plurality of word lines and the strings and is configured to periodically determine a read frequency metric associated with a plurality of read operations of one of the plurality of blocks of the memory cells. The control means is also configured to relocate data of the one of the plurality of blocks and cause the one of the plurality of blocks to remain unused for a predetermined relaxation time based on the read frequency metric.

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 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: Technology for two-sided adjacent memory cell interference mitigation in a non-volatile storage system is disclosed. During reading of target memory cells, the storage system applies a suitable magnitude read pass voltage to a first unselected word line adjacent to a target word line to compensate for interference from adjacent cells on the first unselected word line while applying a suitable magnitude read reference voltage to the target word line to compensate for interference from adjacent cells on a second unselected word line on the other side of the target word line. The read pass voltage may compensate for interference due to charge being added to when programming cells on the first unselected word line after programming the target cells. The read reference voltage may compensate for interference due to charge movement near the target cells that results from charge stored in the cells on the second unselected word line.

Abstract: A method for trimming analog temperature sensors. First, raise a temperature of a temperature sensor to a highest temperature of a qualification temperature range. Then, trim the temperature sensor such that a high temperature code generated by the temperature sensor represents an actual temperature reported by the temperature sensor at the highest temperature. Next, lower the temperature of the temperature sensor to a lowest temperature of the qualification temperature range. Determine a slope error between the high temperature code and a low temperature code generated by the temperature sensor at the lowest temperature. Finally, determine a correction function that compensates for the slope error of measured temperature codes generated by the temperature sensor for temperatures across the qualification temperature range.

Abstract: Non-volatile memory structures for performing compute in memory inferencing for neural networks are presented. To improve performance, both in terms of speed and energy consumption, weight matrices are replaced with their singular value decomposition (SVD) and use of a low rank approximations (LRAs). The decomposition matrices can be stored in a single array, with the resultant LRA matrices requiring fewer weight values to be stored. The reduced sizes of the LRA matrices allow for inferencing to be performed more quickly and with less power. In a high performance and energy efficiency mode, a reduced rank for the SVD matrices stored on a memory die is determined and used to increase performance and reduce power needed for an inferencing operation.

Abstract: Apparatuses and techniques are described for programming a multi-tier block in which sub-blocks are arranged in respective tiers. When a program operation involves the source-side sub-block, the NAND strings are pre-charged from the source line. When a program operation involves the drain-side sub-block, the NAND strings are pre-charged from the bit line. When a program operation involves an interior sub-block, the NAND strings can be pre-charged from the bit line if all sub-blocks on the drain side of the interior sub-block are erased, or from the source line if all sub-blocks on the source side of the interior sub-block are erased. A table can be provided which identifies free blocks, free sub-blocks and a corresponding program order. If such a table is not available, the sub-blocks can be read to determine whether they are programmed.

Abstract: Techniques are presented for performing in-memory matrix multiplication operations for binary input, binary weight valued convolution neural network (CNN) inferencing. The weights of a filter are stored in pairs of memory cells of a storage class memory device, such as a ReRAM or phase change memory based devices. To reduce current consumption, the binary valued filters are transformed into ternary valued filters by taking sums and differences of binary valued filter pairs. The zero valued weights of the transformed filters are stored as a pair of high resistance state memory cells, reducing current consumption during convolution. The results of the in-memory multiplications are pair-wise combined to compensate for the filter transformations. To compensate for zero valued weights, a zero weight register stores the number of zero weights along each bit line and is used to initialize counter values for accumulating the multiplication operations.

Abstract: A non-volatile memory system erasing groups of connected memory cells separately performs erase verify for memory cells connected to even word lines to generate even results and erase verify for memory cells connected to odd word lines to generate odd results. The even results and the odd results are used to determine if the erase verify process indicates that the erasing has successful completed. In addition, for each group of connected memory cells, a last even result for the group is compared to a last odd result for the group. Even if the erase verify indicated that the erasing has successfully completed, the system may determine that the erasing failed (i.e. due to a defect) if the number of groups of connected memory cells that have the last even result different than the last odd result is greater than a limit.

Abstract: A method of erasing memory cells in a memory device is provided. The method includes grouping a plurality of word lines into a first group, which does not include edge word lines, and a second group, which does include edge word lines. An erase operation is performed on the memory cells of the first and second groups until erase-verify of the memory cells of the first group passes. It is then determined if further erase of the memory cells of the second group is necessary. In response to it being determined that the additional erase operation is necessary, an additional erase operation is performed on at least some of the memory cells of the second group until erase-verify of the memory cells of the second group passes.