Apparatuses and techniques are described for obtaining a threshold voltage distribution for a set of memory cells based on a user read mode. The user read mode can be based on various factors including a coding of a page and an increasing or decreasing order of the read voltages. The read process for the Vth distribution is made to mimic the read mode which is used when the memory device is in the hands of the end user. This results in a Vth distribution which reflects the user's experience to facilitate troubleshooting. In some cases, one or more dummy read operations are performed, where the read result is discarded, prior to a read operation which is used to build the Vth distribution.

A high resolution impedance adjustment (ZQ) calibration method using a hidden least significant bit (HLSB) is provided. The high resolution ZQ calibration method generates a data input/output (DQ) code of n+1 bits without a calibration time increase by adding the hidden least significant bit (HLSB) to a ZQ code of n bits output in a ZQ calibration operation of an impedance adjustment (ZQ) pad. A change in a termination resistance of the DQ pad is reduced as small as possible by the DQ code of n+1 bits.

According to one embodiment, a memory system includes a non-volatile memory and a controller. The memory includes a plurality of storage areas. Each of the storage areas includes a plurality of memory cells to which threshold voltages are set in accordance with data. The controller acquires a first threshold voltage distribution of memory cells in a first storage area of the storage areas. The controller acquires a second threshold voltage distribution of memory cells in a second storage area of the storage areas. The controller detects non-normalcy in the first storage area or the second storage area from a first divergence quantity between the first threshold voltage distribution and the second threshold voltage distribution.

Exemplary methods, apparatuses, and systems include receiving a plurality of read operations. The read operations are divided into a current set of a sequence of read operations and one or more other sets. The size of the current set is a first number of read operations. An aggressor read operation is selected from the current set. A first data integrity scan is performed on a victim of the aggressor and a first indicator of data integrity is determined based on the first data integrity scan. A scaling factor is determined using the indicator of data integrity and a number of program erase cycles for the portion of memory. The set size of read operations is adjusted to a second number of read operations using the scaling factor for a subsequent set.

Memory array structures providing for determination of resistive characteristics of access lines might include a first block of memory cells, a second block of memory cells, a first current path between a particular access line of the first block of memory cells and a particular access line of the second block of memory cells, and, optionally, a second current path between the particular access line of the second block of memory cells and a different access line of the first block of memory cells. Methods for determining resistive characteristics of access lines might include connecting the particular access line of the first block of memory cells to a driver, and determining the resistive characteristics in response to a current level through that access line and a voltage level of that access line.

Memory devices, systems including memory devices, and methods of operating memory devices are described, in which memory devices are configured to monitor word line characteristics. In one embodiment, the memory device includes a memory array including a word line (e.g., a local word line) and a word line driver coupled thereto. When the memory device activates the word line driver, the memory device may generate a diagnostic signal in response to the word line voltage reaching a threshold. Further, the memory device may generate a reference signal to compare the diagnostic signal with the reference signal. In some cases, the memory device may generate an alert signal based on comparing the diagnostic signal with the reference signal if the diagnostic signal indicates a symptom of degradation in the word line characteristics. The memory device may implement certain preventive and/or precautionary measures upon detecting the symptom.

Self-repair logic for stacked memory architecture. An embodiment of a memory device includes a memory stack having one or more memory die elements, including a first memory die element, and a system element coupled with the memory stack. The first memory die element includes multiple through silicon vias (TSVs), the TSVs including data TSVs and one or more spare TSVs, and self-repair logic to repair operation of a defective TSV of the plurality of data TSVs, the repair of operation of the defective TSV including utilization of the one or more spare TSVs.

An improved sensing circuit is disclosed that utilizes a bit line in an unused memory array to provide reference values to compare against selected cells in another memory array. A circuit that can perform a self-test for identifying bit lines with leakage currents about an acceptable threshold also is disclosed.

A nonvolatile memory device includes a memory cell array, a voltage generator, a voltage path circuit and a wordline defect detection circuit. The memory cell array includes memory cells and wordlines connected to the memory cells. The voltage generator generates a wordline voltage applied to the wordlines. The voltage path circuit between the voltage generator and the memory cell array transfers the wordline voltage to the wordlines. The wordline defect detection circuit is connected to a measurement node between the voltage generator and the voltage path circuit. The wordline defect detection circuit measures a path leakage current of the voltage path circuit based on a measurement voltage of the measurement node to generate an offset value corresponding to the path leakage current in a compensation mode and determines defect of each wordline of the wordlines based on the offset value and the measurement voltage in a defect detection mode.

Methods, systems, and devices for initializing memory systems are described. A memory system may transmit, to a host system over a first channel, signaling indicative of a first set of values for a set of parameters associated with communicating information over a second channel between a storage device of the memory system and a memory device of the memory system. The host system may transmit, to the memory system, additional signaling associated with the first set of values for the set of parameters. For instance, the host system may transmit a second set of values for the set of parameters, an acknowledgement to use the first set of values, or a command to perform a training operation on the second channel to identify a second set of values for the set of parameters. The memory system may communicate the information over the second channel based on the additional signaling.