A memory device includes a mode register set configured to store a first repair mode, a second repair mode, and a second repair off mode, and a repair control circuit configured to perform a first repair operation for permanently repairing a first wordline corresponding to a defective address to a first redundancy wordline in the first repair mode, to perform a second repair operation for temporarily repairing the first wordline corresponding to the defective address to a second redundancy wordline in the second repair mode, and to turn off a repair logic that is configured to perform the second repair operation in the second repair off mode to access old data after the second repair operation.

A method of testing a memory device, a memory built-in self-test (MBIST) circuit, and a memory device for improving reliability and reducing a test time. The memory device includes a plurality of memory banks and the MBIST circuit. The MBIST circuit is configured to generate double data rate (DDR) test patterns and parallel bit test (PBT) test patterns to test the memory banks. When a defective cell is detected as a result of the PBT test or the DDR test, the MBIST circuit is configured to perform a repair operation for replacing the defective cell with a redundancy cell and perform a re-test to verify the repair operation. The MBIST circuit may be configured to perform the DDR test on one or more memory cells including the defective cell during the re-test.

A local region to be repaired including the fail bit is determined. A preliminary repair LR circuit for repairing the local region to be repaired is determined (S210). A region level of the local region to be repaired is determined (S230) according to the number of available GR circuits other than any replacement GR circuit configured for replacing the preliminary repair LR circuit and the number of available LR circuits. It is controlled, according to the region level of the local region to be repaired, to repair the fail bit by the GR circuit or the LR circuit (S240).

Apparatuses, systems, and methods for fuse based device identification. A device may include a number of fuses which are used to encode permanent information on the device. The device may receive an identification request, and may generate an identification number based on the states of at least a portion of the fuses. For example, the device may include a hash generator, which may generate the identification number by using the fuse information as a seed for a hash algorithm.

A memory test method and apparatus, an electronic device, and a computer-readable storage medium are provided. The method includes: obtaining a test instruction; generating, in response to the test instruction, a test clock signal, a to-be-tested address and to-be-tested data; determining a to-be-tested memory from memories of a storage device, the storage device including a self-test circuit; writing the to-be-tested data into a storage unit corresponding to the to-be-tested address of the to-be-tested memory; reading output data from the storage unit corresponding to the to-be-tested address of the to-be-tested memory; and comparing the to-be-tested data and the output data to obtain a test result of the to-be-tested memory. The self-test circuit disposed in the storage device is used to implement a memory test process. Thus, the dependency on automatic test equipment is reduced, thereby improving test speed and reducing test cost.

Embodiments of the disclosure are drawn to apparatuses and methods for soft post-package repair (SPPR). After packaging, it may be necessary to perform post-package repair operations on rows of the memory. During a scan mode of an SPPR operation, addresses provided by a fuse bank may be examined to determine if they are open addresses or if the bad row of memory is a redundant row of memory. The open addresses and the bad redundant addresses may be stored in volatile storage elements, such as in latch circuits. During a soft send mode of a SPPR operation, the address previously associated with the bad row of memory may be associated with the open address instead, and the address of the bad redundant row may be disabled.

Methods, apparatuses and systems related to managing access to a memory device are described. A memory device includes fuses and latches for storing a repair segment locator and a repair address for each repair of one or more defective memory cells. A segment-address determination circuit generate an active segment address based on the repair address according to the repair segment locator and an address for a read or a write operation. A comparator circuitry is configured to determine whether the active segment address matches the address for the read or the write operation for replacing the one or more defective memory cells with the plurality of redundant cells when the address for the read/write operation corresponds to the one or more defective memory cells.

A method of managing errors in a plurality of storage drives includes receiving, at a memory controller coupled to at least one storage medium in an SSD, a read command from a host interface. The method also includes retrieving, from the storage medium, read data corresponding to a plurality of data chunks to be retrieved in response to the read command, and determining that at least one data chunk of the plurality of data chunks is unable to be read, the at least one data chunk corresponding to a failed data chunk. And in response to determining the failed data chunk, sending to the host interface the read data including the failed data chunk or excluding the failed data chunk. And in response to the read command sending to the host interface status information about all data chunks.

A semiconductor memory device has a memory cell array area including a normal area including memory blocks and a redundant memory area including a redundant block which is a replacement target of a defective block among memory blocks; a storage unit storing address information indicating a position of the defective block in the normal area and address information indicating a position of the redundant block being the replacement target of the defective block, both being in association with each other as a first information; and an output circuit outputting a data row exhibiting a positional relation between the defective block and a memory block other than the defective block in the normal area based on the first information stored in the storage unit in response to the data read signal.

A method of managing errors in a plurality of storage drives includes receiving, at a memory controller coupled to at least one storage medium in an SSD, a read command from a host interface. The method also includes retrieving, from the storage medium, read data corresponding to a plurality of data chunks to be retrieved in response to the read command, and determining that at least one data chunk of the plurality of data chunks is unable to be read, the at least one data chunk corresponding to a failed data chunk. And in response to determining the failed data chunk, sending to the host interface the read data including the failed data chunk or excluding the failed data chunk. And in response to the read command sending to the host interface status information about all data chunks.