Patent classifications
G11C16/3404
STORAGE DEVICES AND METHODS OF OPERATING STORAGE DEVICES
A storage device includes a NAND flash memory device, an auxiliary memory device and a storage controller to control the NAND flash memory device and the auxiliary memory device. The storage controller includes a processor, an error correction code (ECC) engine and a memory interface. The processor executes a flash translation layer (FTL) loaded onto an on-chip memory. The ECC engine generates first parity bits for user data to be stored in a target page of the NAND flash memory device based on error attribute of a target memory region associated with the target page, and selectively generates additional parity bits for the user data under control of the processor. The memory interface transmits the user data and the first parity bits to the NAND flash memory device, and selectively transmits the additional parity bits to the auxiliary memory device.
Determining voltage offsets for memory read operations
A processing device of a memory sub-system is configured to identify a read level of a plurality of read levels associated with a voltage bin of a plurality of voltage bins of a memory device; assign a first threshold voltage offset to the read level of the voltage bin; assign a second threshold voltage offset to the read level of the voltage bin; perform, on block associated with the read level, a first operation of a first operation type using the first threshold voltage offset; and perform, on the blocks associated with the read level, a second operation of a second operation type using the second threshold voltage offset.
Memory system configured to determine a write voltage applied to memory cells based on the number of erase operations
A memory system includes a semiconductor storage device including a memory cell array including a plurality of groups of memory cells, and a control circuit configured to perform, upon receipt of a write command, a write operation on one of the groups of memory cells, and a memory controller is configured to, when transmitting the write command to perform the write operation on the one of the groups of memory cells, determine a first write voltage value for the write operation based on a total number of write operations or erase operations that have been performed on the one of the groups of memory cells, and transmit the write command to the semiconductor storage device together with the determined first write voltage value.
LATCH BIT CELLS
A bit cell of an SRAM implemented using standard cell design rules includes a write portion and a read portion. The write portion includes a pass gate coupled to an input node of the bit cell and supplies data on the input node to a first node of the bit cell while write word line signals are asserted. An inverter is coupled to the first node and supplies inverted data. A keeper circuit that is coupled to the inverter maintains the data on the first node when the write word line signals are deasserted. The read portion of the bit cell receives read word line signals and the inverted data and is responsive to assertion of the read word line signals to supply an output node of the read portion of the bit cell with output data that corresponds to the data on the first node.
PHYSICAL UNCLONABLE FUNCTION WITH NAND MEMORY ARRAY
Various examples described herein are directed to systems and methods for generating data values using a NAND flash array. A memory controller may read a number of memory cells at the NAND flash array using an initial read level to generate a first raw string. The memory controller may determine that a difference between a number of bits from the first raw string having a value of logical zero and a number of bits from the first raw string having a value of logical one is greater than a threshold value and read the number of memory cells using a second read level to generate a second raw string. The memory controller may determine that a difference between a number of bits from the second raw string having a value of logical zero and a number of bits from the second raw string having a value of logical one is not greater than a threshold value and applying a cryptographic function using the second raw string to generate a first PUF value.
STABILIZATION OF SELECTOR DEVICES IN A MEMORY ARRAY
A variety of applications can include memory devices designed to provide stabilization of selector devices in a memory array of the memory device. A selector stabilizer pulse can be applied to a selector device of a string of the memory array and to a memory cell of multiple memory cells of the string with the memory cell being adjacent to the selector device in the string. The selector stabilizer pulse can be applied directly following an erase operation to the string to stabilize the threshold voltage of the selector device. The selector stabilizer pulse can be applied as part of the erase algorithm of the memory device. Additional devices, systems, and methods are discussed.
Method for managing requests for access to random access memory and corresponding system
A random access memory is connected to a processing unit through a memory interface. Access to the random access is memory is controlled by a process. The memory interface receives a request for access to the memory issued by the processing unit. In response to the request, the memory interface indicates to the processing unit that the memory is not available to receive another access request during a duration of unavailability. This duration can be differentiated depending on whether the received request is a write or read request. The value of the duration of unavailability associated with a write request and the value of the duration of unavailability associated with a read request are individually programmable independently of each other.
Memory apparatus and method of operation using periodic normal erase dummy cycle to improve stripe erase endurance and data retention
A memory apparatus and method of operation are provided. The apparatus includes memory cells connected to one of a plurality of word lines and arranged in strings and configured to retain a threshold voltage corresponding to one of a plurality of memory states. A control circuit is coupled to the plurality of word lines and strings and is configured to erase the memory cells using a stripe erase operation in response to determining a cycle count is less than a predetermined cycle count maximum threshold. The control circuit is also configured to perform a dummy cycle operation in response to determining the cycle count is not less than the predetermined cycle count maximum threshold.
MULTI-PROGRAM OF MEMORY CELLS WITHOUT INTERVENING ERASE OPERATIONS
A memory device includes an array of memory cells configured as single-level cell memory and control logic operatively coupled with the array of memory cells. The control logic is to perform operations including: causing first data to be programmed to a plurality of memory cells of the array of memory cells, the first data including a first erase distribution programmed below an erase threshold voltage (Vt) level and a first voltage distribution programmed relative to a first Vt level; and causing, without erasing the plurality of memory cells, second data to be programmed to the plurality of memory cells, the second data including a second erase distribution programmed relative to the first Vt level and a second voltage distribution programmed relative to a second Vt level.
MEMORY SYSTEM
A memory system according to an embodiment includes a nonvolatile memory and a memory controller. The nonvolatile memory includes a plurality of memory cells. The memory controller is configured to control the nonvolatile memory. In read operation for the memory cells, the memory controller is configured to: perform tracking including a plurality of reads in which a read voltage is shifted; determine a hard bit read voltage based on results of the tracking; calculate a soft bit read voltage based on the determined hard bit read voltage; perform soft bit read using the calculated soft bit read voltage; and perform a soft bit decoding process using a result of the soft bit read and a log-likelihood ratio table associated with the calculated soft bit read voltage.