Abstract: Methods, systems, and devices for targeted command/address parity low lift are described. A memory device may receive a command (e.g., a write command or a read command) from a host device over a first set of pins and may perform data transfer over a second set of pins with the host device during a set of time intervals according to the command. The memory device may exchange a parity bit associated with the command with the host device over a third set of pins during a first time intervals of the set of time intervals. In some cases, the third memory device may exchange at least one additional bit associated with the command with the host device during at least one time interval of the set of time intervals.

Abstract: Methods, systems, and devices for metadata storage at a memory device are described to support storage of metadata information and error control information at a memory device. The metadata information and error control information may be received at the memory device via a sideband channel and corresponding pin. For example, a set of bits received via the pin may include a subset of error control bits and a subset of metadata bits. Circuitry at the memory device may receive the set of bits via the pin and may identify metadata information and error control information within the set of bits. The circuitry may route the metadata information to a corresponding subset of memory cells and the error control information to an error control circuit, where the error control circuit may route the error control information to a corresponding subset of memory cells.

Abstract: Methods, systems, and devices for host error control matrix are described. A host device may implement a parity check matrix for generating error control information with a relatively low likelihood that a multi-bit error in a codeword associated with the error control information is mistaken for a single-bit error. The host device may implement a parity check matrix patterned such that when the error control information is generated, there is a relatively low likelihood that an error code resulting from a comparison of the error control information will yield an indication of a single-bit error when a multi-bit error occurs. For example, the host device may compare first error control information generated for a codeword and transmitted to a memory device with second error control information generated after receiving the codeword from the memory device, and generate an error code using the results of the comparison.

Abstract: Implementations described herein relate to performing a memory built-in self-test and indicating a status of the memory built-in self-test. A memory device may read one or more bits, associated with a memory built-in self-test, that are stored in a mode register of the memory device. The memory device may identify, based on the one or more bits, that the memory built-in self-test is enabled. The memory device may set a DMI bit of the memory device to a first value and perform the memory built-in self-test based on identifying that the memory built-in self-test is enabled. The memory device may set the DMI bit of the memory device to a second value based on a completion of the memory built-in self-test.

Abstract: Implementations described herein relate to command address fault detection using a parity bit. A memory device may receive, from a host device via a command address (CA) bus and during a unit interval, a set of CA bits associated with a CA word. The memory device may receive, from the host device via a parity bus and during the unit interval, a first parity bit that is based on the set of CA bits and a parity generation process. The memory device may generate a second parity bit based on the set of CA bits and the parity generation process. The memory device may compare the first parity bit and the second parity bit. The memory device may selectively transmit an alert signal to the host device based on a result of comparing the first parity bit and the second parity bit.

Abstract: Methods, systems, and devices for internal error correction for memory devices are described. A memory device may perform a read operation at a memory array having a data partition and an error check partition and may obtain a first set of bits from the data partition and a second set of bits from the error check partition. The memory device may determine a first error detection result based on a value of a determined syndrome. The memory device may obtain a parity bit from the first set of bits and determine a second error detection result based on a comparison of the parity bit with a second function of the subset of the first set of bits. The memory device may transmit the first set of bits to a host device based at least in part on the first and second error detection results.

Abstract: Methods, systems, and devices for error detection and classification at a host device are described. A host device may communicate a read command for a codeword stored at a memory device. In response to communicating the read command, the host device may receive the codeword and an error indication bit that indicates whether the memory device detected an error in the codeword. The host device may use the codeword to generate a set of syndrome bits. The host device may determine an error status of the codeword based on the error indication bit for the codeword and the set of syndrome bits for the codeword.

Abstract: Implementations described herein relate to refresh rate selection for a memory built-in self-test. A memory device may read one or more bits, associated with the memory built-in self-test, that are stored in a mode register of the memory device. The memory device may identify, based on the one or more bits, a refresh rate to be used while performing the memory built-in self-test. The refresh rate may indicate a rate at which memory cells, to be tested by the memory built-in self-test, are to be refreshed while the memory built-in self-test is being performed. The memory device may perform the memory built-in self-test while refreshing the memory cells according to the refresh rate.

Abstract: Methods, systems, and devices for syndrome check functionality to differentiate between error types are described. A host system, a memory system, or some combination of both may include syndrome check circuitry to provide enhanced error diagnostic capabilities for data communicated between the host system and the memory system. The syndrome check circuitry may receive a first signal from the memory system indicating whether the memory system detected and attempted to correct an error in the data and may receive a second signal from the host system indicating whether the host system detected an error in the received data. The syndrome check circuitry may compare the first signal and the second signal using a set of logic gates to differentiate between different combinations of errors detected at one or both of the memory system or the host system.

Abstract: Methods, systems, and devices for memory operations are described. A read command may be received at a memory device from a host device. As part of an error control operation, a first set of error control bits may be generated for the set of data. Based on the first set of error control bits, a failure of a matching operation associated with the error control operation may be determined. Based on determining the failure of the matching operation, a second set of error control bits that is different than the first set of error control bits may be transmitted to the host device. The second set of error control bits may indicate that the matching operation failed at the memory device.

Abstract: Methods, systems, and devices for metadata storage at a memory device are described to support storage of metadata information and error control information at a memory device. The metadata information and error control information may be received at the memory device via a sideband channel and corresponding pin. For example, a set of bits received via the pin may include a subset of error control bits and a subset of metadata bits. Circuitry at the memory device may receive the set of bits via the pin and may identify metadata information and error control information within the set of bits. The circuitry may route the metadata information to a corresponding subset of memory cells and the error control information to an error control circuit, where the error control circuit may route the error control information to a corresponding subset of memory cells.

Abstract: Methods, systems, and devices for targeted command/address parity low lift are described. A memory device is configured to receive a command (e.g., a write command or a read command) from a host device over a first set of pins and is configured to perform data transfer over a second set of pins with the host device during a set of time intervals according to the command. The memory device is configured to exchange a parity bit associated with the command with the host device over a third set of pins during a first time intervals of the set of time intervals. In some cases, the third memory device is configured to exchange at least one additional bit associated with the command with the host device during at least one time interval of the set of time intervals.

Abstract: Methods, systems, and devices for operational monitoring for memory devices are described. Some memory devices may degrade over time, and this degradation may include or refer to a reduction of an ability of the memory device to reliably store, read, process, or communicate information, among other degradation. In accordance with examples as disclosed herein, a memory device may include components configured for monitoring health or life expectancy or both of the memory device, such as components internal to the memory device that identify and store various indications of a duration of operating a memory device. An operational duration stored at the memory device may be used in various operations, such as calculations or comparisons, to evaluate health or life expectancy of the memory device, which may include or be supported by various signaling with a host device.

Abstract: Methods, systems, and devices for techniques for detecting a state of a bus are described. A memory device may fail to receive or decode (e.g., successfully receive or successfully decode) an access command transmitted to the memory device via a bus. The bus may enter or remain in an idle state which may cause indeterminate signals to develop on the idle bus. A host device may obtain the indeterminate signals from the idle bus and determine that the indeterminate signals include an error based on a signal that develops on a control line of the idle bus. The signal may be associated with a control signal that indicates errors in a data signal when the control signal has a first voltage, and the control line may be configured to have the first voltage when the bus is idle.

Abstract: Methods, systems, and devices for memory traffic monitoring are described. The monitoring may include traffic monitoring of access operations performed at various components of the memory device, or may include sensors that may measure parameters of components of the memory device to detect wear. The traffic monitoring or the parameters measured by the sensors may be represented by a characteristic related to an operational bias of circuits of the memory device. The memory device may use the characteristic (e.g., along with a threshold) to determine whether to adjust a parameter associated with performing access operations received by the memory device, in order to implement a corrective action.

Abstract: Methods, systems, and devices for error log indication via error control information are described. For instance, a memory device may transmit, to a host device, a first signal including a set of error control bits indicating that an error log of the memory device includes information for use by the host device. The memory device may receive, from the host device in response to the first signal, a second signal including a request to retrieve the information of the error log. The memory device may transmit, to the host device in response to the second signal, a third signal including the information of the error log.

Abstract: Methods, systems, and devices for memory fault notification are described. A memory device may receive a configuration corresponding to a circuit node of the memory device, where the circuit node may be selectively coupled with a set of resistors. The memory device may determine a fault condition and couple the circuit node to at least a first resistor based on determining the fault condition. The memory device may bias the circuit node to a first voltage value that satisfies a voltage threshold based on coupling the circuit node to the first resistor. The memory device may output an indication of a fault state to notify a host device that a fault has been detected.

Abstract: Methods, systems, and devices for error status determination at a memory device are described. A memory device may generate, based on syndrome bits for a codeword read from a memory, an error detection signal for the codeword that indicates whether an error has been detected in the codeword. The memory device may generate, based on the syndrome bits, an error correction signal for the codeword that indicates whether an error has been corrected in the codeword. And the memory device may provide an indication of the error detection signal and an indication of the error correction signal to a host device.

Abstract: Methods, systems, and devices for internal error correction for memory devices are described. A memory device may perform a read operation at a memory array having a data partition and an error check partition and may obtain a first set of bits from the data partition and a second set of bits from the error check partition. The memory device may determine a first error detection result based on a value of a determined syndrome. The memory device may obtain a parity bit from the first set of bits and determine a second error detection result based on a comparison of the parity bit with a second function of the subset of the first set of bits. The memory device may transmit the first set of bits to a host device based at least in part on the first and second error detection results.

Abstract: Methods, systems, and devices for selective modes for error control are described. A memory system may implement an error control engine supporting error correction operations and error detection operations. The error control engine may switch between an error correction mode and an error detection mode. The error control engine may receive data and error control information, generate additional error control information, and compare the received and generated error control information to detect one or more errors in the data. In some examples, the error control engine may be configured to operate in the error correction mode, and the error control engine may correct single-bit errors in the data. In other examples, the error control engine may be configured to operate in the error detection mode, and the error control engine may detect errors in the data and transmit an indication of the errors.