Embodiments combine error correction code (ECC) and transparent memory built-in self-test (TMBIST) for memory fault detection and correction. An ECC encoder receives input data and provides ECC data for data words stored in memory. Input XOR circuits receive the input data and output XOR'ed data as payload data for the data words. Output XOR circuits receive the payload data and output XOR'ed data. An ECC decoder receives the ECC data and the XOR'ed output data and generates error messages. Either test data from a controller running a TMBIST process or application data from a processor executing an application is selected as the input data. Either test address/control signals from the controller or application address/control signals from the processor are selected for memory access. During active operation of the application, memory access is provided to the processor and the controller, and the memory is tested during the active operation.

Embodiments combine error correction code (ECC) and transparent memory built-in self-test (TMBIST) for memory fault detection and correction. An ECC encoder receives input data and provides ECC data for data words stored in memory. Input XOR circuits receive the input data and output XOR'ed data as payload data for the data words. Output XOR circuits receive the payload data and output XOR'ed data. An ECC decoder receives the ECC data and the XOR'ed output data and generates error messages. Either test data from a controller running a TMBIST process or application data from a processor executing an application is selected as the input data. Either test address/control signals from the controller or application address/control signals from the processor are selected for memory access. During active operation of the application, memory access is provided to the processor and the controller, and the memory is tested during the active operation.

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.

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.

A memory subsystem has multiple memory devices coupled to a command/address line and an error alert line, the error alert line delay-compensated to provide deterministic alert signal timing. The command/address line and the error alert line are connected between the memory devices and a memory controller that manages the memory devices. The command/address line is driven by the memory controller, and the error alert line is driven by the memory devices.

A memory subsystem has multiple memory devices coupled to a command/address line and an error alert line, the error alert line delay-compensated to provide deterministic alert signal timing. The command/address line and the error alert line are connected between the memory devices and a memory controller that manages the memory devices. The command/address line is driven by the memory controller, and the error alert line is driven by the memory devices.

A method of correcting errors in a memory array. The method includes configuring a first memory array with a first error correction code (ECC) to provide error correction of data stored in the first memory array, configuring a second memory array with a second ECC to provide error correction of the data stored in the first memory array, performing a reflow process on the first and second memory array, and correcting data stored in the first memory array based on at least the first ECC or the second ECC. The first memory array includes a first set of memory cells arranged in rows and columns. The second memory array includes a second set of memory cells arranged in rows and columns.

Writing time is shortened even in a memory writing time for each access unit is not constant. A writing time prediction information holding unit holds writing time prediction information for predicting the writing time in a plurality of memory modules for each of a plurality of memory modules. A request selecting unit preferentially selects a write request of which longer writing time is predicted out of a plurality of write requests requiring writing in each of a plurality of memory modules on the basis of the writing time prediction information.

Systems, apparatuses, and methods for transmission failure feedback associated with a memory device are described. A memory device may detect errors in received data and transmit an indication of the error when detected. The memory device may receive data and checksum information for the data from a controller. The memory device may generate a checksum for the received data and may detect transmission errors. The memory device may transmit an indication of detected errors to the controller, and the indication may be transmitted using a line that is different than an error detection code (EDC) line. A low-speed tracking clock signal may also be transmitted by the memory device over a line different than the EDC line. The memory device may transmit a generated checksum to the controller with a time offset applied to the checksum signaled over the EDC line.

Systems, apparatuses, and methods for transmission failure feedback associated with a memory device are described. A memory device may detect errors in received data and transmit an indication of the error when detected. The memory device may receive data and checksum information for the data from a controller. The memory device may generate a checksum for the received data and may detect transmission errors. The memory device may transmit an indication of detected errors to the controller, and the indication may be transmitted using a line that is different than an error detection code (EDC) line. A low-speed tracking clock signal may also be transmitted by the memory device over a line different than the EDC line. The memory device may transmit a generated checksum to the controller with a time offset applied to the checksum signaled over the EDC line.