Abstract: An apparatus that includes a word line with a plurality of memory cells that are able to be programmed to a plurality of data states is provided. The apparatus further includes a programming circuit. The programming circuit is configured to program count the number of verify pulses at a first verify voltage level that are performed during programming of the memory cells to a first programmed data state to determine a verify count. During programming to a second data state, the programming circuit applies a plurality of programming pulses at increasing voltage levels and a plurality of verify pulses at a second verify voltage level to the selected word line. During programming of the memory cells to the second programmed data state, the number of verify pulses is one fewer than the number of programming pulses.

Abstract: Non-volatile memory structures are presented for a content addressable memory (CAM) that can perform in-memory search operations for both ternary and binary valued key values. Each ternary or binary valued key bit is stored in a pair of memory cells along a bit line of a NAND memory array, with the stored keys searched by applying each ternary or binary valued bit of an input key as voltage levels on a pair of word lines. The system is highly scalable. The system can also be used to perform nearest neighbor searches between stored vectors and an input vector to find stored vectors withing a specified Hamming distance of the input vector.

Abstract: Technology for sensing non-volatile memory cells in which one or more sense nodes are charged to a sense voltage having a magnitude that improves sensing accuracy. One sense node may be charged to different sense voltages when sensing different memory cells at different times. Multiple sense nodes may be charged to a corresponding multiple different sense voltages when sensing different memory cells at the same time. The one or more sense nodes are allowed to discharge based on respective currents of memory cells for a pre-determined time while applying a reference voltage to the memory cells. The Vts of the selected memory cells are assessed based on respective voltages on the one or more of sense nodes after the pre-determined time. Different sensing voltages may be used based on bit line voltage, bit line resistance, distance of memory cells from the sense node, or other factors.

Abstract: Systems and methods for reducing the size of sub-blocks within a physical memory block for a three-dimensional non-volatile memory using buried source lines are described. The physical memory block may be fabricated using dual buried source lines such that sub-blocks within the physical memory block may be individually selected in both a horizontal word line direction and a vertical NAND string direction. The physical memory block may include a plurality of sub-blocks that are individually selectable and that share bit lines and/or source-side select gate lines. The plurality of sub-blocks that are individually selectable may correspond with different portions of the same NAND string in which a first sub-block of the plurality of sub-blocks connects to a drain-side select gate for the NAND string and a second sub-block of the plurality of sub-blocks connects to a source-side select gate for the NAND string.

Abstract: An apparatus and method for detecting leakage current in a non-volatile memory array. A reference current is connected to a leakage detection circuit. A reference code is determined for the leakage detection circuit coupled to a switching circuit. The reference code establishes a leakage current threshold. The reference current is disconnected from the leakage detection circuit and the switching circuit. Next, the leakage detection circuit is connected to a set of word lines of a storage block of a non-volatile memory array by way of the switching circuit. A memory current is generated within the set of word lines. A leakage code is determined for the set of word lines representing leakage current from the word lines in response to the memory current. The leakage code is compared with the reference code. If the leakage code exceeds the reference code, the storage block is deemed unusable.

Abstract: A memory apparatus and method of operation are provided. The apparatus includes memory cells each connected to a word line and arranged in one of a plurality of blocks and configured to retain a threshold voltage corresponding to a data state. The memory cells are operable in one of a first read condition in which a word line voltage is discharged and a second read condition in which the word line voltage is coupled up to a residual voltage level. A control circuit determines a power on event and periodically apply a predetermined refresh read voltage to the word line for a predetermined period of time for each of the plurality of blocks at a specified interval based on at least one data retention factor to maintain the memory cells of the plurality of blocks in the second read condition in response to determining the power on event.

Abstract: A non-volatile memory includes a non-volatile memory array comprising blocks of non-volatile memory cells, bit lines connected to the memory cells and word lines connected to the memory cells. Word line switch transistors connect the word lines to voltage sources. The word line switch transistors are positioned in triple wells. Multiple triple wells are utilized and the word line switch transistors are grouped into triple wells based on word line voltage ranges used during the programming process. In one embodiment, for a given block, the word line switch transistors connected to data word lines are positioned in a first triple well and the word line switch transistors connected to selection and dummy word lines are positioned in a second triple well. This structure allows the triple wells to be biased differently.

Abstract: A method for a pre-lockout read for a reverse order read operation with lockout mode is disclosed. The method comprises: performing a pre-lockout read at a first sensing level to determine which memory cells of the set of memory cells are on in response to the first sensing level being applied to a selected word line; performing a first sensing operation on the selected word line at a second sensing level including sensing memory cells of the set of memory cells determined to be off in response to the pre-lockout read; and performing a second sensing operation on the selected word line at a third sensing level including sensing memory cells of the set of memory cells determined to be on in response to the pre-lockout read, where the first sensing level is of a value between the second sensing level and the third sensing level.

Abstract: For a non-volatile memory die formed of multiple blocks of memory cells, the memory die has a multi-bit bad block flag for each block stored on the memory die, such as in a fuse ROM. For each block, the multi-bit flag indicates if the block has few defects and is of the highest reliability category, is too defective to be used, or is in of one of multiple recoverability categories. The multi-bit bad blocks values can be determined as part a test process on fresh devices, where the test of a block can be fail stop for critical category errors, but, for recoverable categories, the test continues and tracks the test results to determine a recoverability category for the block and write this onto the die as a bad block flag for each block. These recoverability categories can be incorporated into wear leveling operations.

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 non-volatile memory structure capable of storing layers of a deep neural network (DNN) and perform an inferencing operation within the structure is presented. A stack of bonded die pairs is connected by through silicon vias. Each bonded die pair includes a memory die, having one or more memory arrays onto which layers of the neural network are mapped, and a peripheral circuitry die, including the control circuits for performing the convolution or multiplication for the bonded die pair. The multiplications can either be done in-array on the memory die or in-logic on the peripheral circuitry die. The arrays can be formed into columns along the vias, allowing an inferencing operation to be performed by propagating an input up and down the columns, with the output of one level being the input of the subsequent layer.

Abstract: A non-volatile memory structure capable of storing layers of a deep neural network (DNN) and perform an inferencing operation within the structure is presented. A stack of bonded die pairs is connected by through silicon vias. Each bonded die pair includes a memory die, having one or more memory arrays onto which layers of the neural network are mapped, and a peripheral circuitry die, including the control circuits for performing the convolution or multiplication for the bonded die pair. The multiplications can either be done in-array on the memory die or in-logic on the peripheral circuitry die. The arrays can be formed into columns along the vias, allowing an inferencing operation to be performed by propagating an input up and down the columns, with the output of one level being the input of the subsequent layer.

Abstract: An apparatus performs vector matrix multiplication (VMM) for an analog neural network (ANN). The apparatus includes a column of NAND flash cells in series, where each NAND flash cell includes a control gate; a bit line connected to the column of NAND flash cells, where a current drawn from the NAND flash cells flows to the bit line; an integrator connected to the bit line; and a controller having programmed instructions to control the column of NAND flash cells by setting the voltage of the control gate of each NAND flash cell.

Abstract: Techniques are provided for mitigating issues of memory hole mis-shape. In one aspect, one or more control circuits are configured to program a group of non-volatile memory cells from an erase state to a plurality of programmed states using a first program parameter. The one or more control circuits measure threshold voltages of the group to determine a severity of memory hole mis-shape in the group. The one or more control circuits program the group from the erase state to the plurality of programmed states using a second program parameter selected based on the severity of the memory hole mis-shape in the group.

Abstract: Technology is disclosed herein for a semiconductor die, and controlling operation of the semiconductor die. In some aspects, a semiconductor die is configured to test an I/O circuit on the semiconductor die. The semiconductor die has an input circuit that compares a voltage signal at one of a first input or a second input with a reference voltage at the other of the first input or the second input to generate an input voltage signal. The first input may be connected to an I/O contact. During a normal mode a control circuit on the die provides a reference voltage to second input. During a test mode, the control circuit internally loops back a test signal from an output circuit to the second input of the input circuit. Thus, the test signal avoids the I/O contact.

Abstract: A data storage system includes a memory including a plurality of memory cells; and control logic configured to receive a first data string and determine a data type of the first data string. If the first data string is a combination command, the control logic obtains a plurality of sub-commands based on the first data string. Meanwhile, the control logic receives a second data string, determines that it represents an address, and decodes the address. While decoding the address or otherwise processing the second data string, the control logic performs a system operation specified by one of the sub-commands. The control logic also performs a memory operation, specified by another of the sub-commands, on one or more of the plurality of memory cells in accordance with the decoded address.

Abstract: A memory apparatus and method of operation is provided. The apparatus includes memory cells connected to word lines and bit lines and arranged in a plurality of planes. The apparatus also includes a control circuit coupled to the word lines and the bit lines and configured to determine whether a program operation of the memory cells involves all of the plurality of planes. In response to the program operation of the memory cells not involving all of the plurality of planes, the control circuit adjusts at least one of a bit line ramp rate of a bit line voltage applied to the bit lines and a word line ramp rate of at least one word line voltage applied to the word lines during the program operation based on a quantity of the plurality of planes associated with the memory cells being program-verified in the program operation.

Abstract: Apparatuses and techniques are described for optimizing programming in a memory device in which memory cells can be programmed using single bit per cell programming and multiple bits per cell programming. In one aspect, a single bit per cell program operation is performed which reduces damage to the memory cells as well as reducing program time. The program operation can omit a pre-charge phase and a verify phase of an initial program loop of a program operation. Instead, a program phase is performed followed by a recovery phase. In one or more subsequent program loops of the single bit per cell program operation, as well as in each program loop of a multiple bit per cell program operation, the program loop includes a pre-charge phase, a program phase, a recovery phase and a verify phase.

Abstract: Apparatuses and techniques are described for reading MRAM memory cells. In a cross-point memory array, each conductive line, such as a bit line or word line, is connected to a transistor pair comprising a pMOSFET in parallel with an nMOSFET. When selecting a memory cell to be read, a voltage of a first conductive line may be pulled up using the pMOSFET while a voltage of a second conductive line is pulled down, e.g., to 0 V, using the nMOSFET. This minimizes a capacitance while the selector is turned on. Further, when reading the selected memory cell, the parallel nMOSFET of the first conductive line may turned on while the pMOSFET is turned off. The nMOSFET provides a higher resistance in place of the decreased resistance of the pMOSFET to amplify a signal at a sense circuit to allow accurate sensing of the voltage across the memory cell.

Abstract: A memory apparatus and method of operation is provided. The apparatus includes memory cells connected to word lines and bit lines and arranged in a plurality of planes. The apparatus also includes a control circuit coupled to the word lines and the bit lines and configured to determine whether a program operation of the memory cells involves all of the plurality of planes. In response to the program operation of the memory cells not involving all of the plurality of planes, the control circuit adjusts at least one of a bit line ramp rate of a bit line voltage applied to the bit lines and a word line ramp rate of at least one word line voltage applied to the word lines during the program operation based on a quantity of the plurality of planes associated with the memory cells being program-verified in the program operation.