A data storage apparatus is provided which has a plurality of data storage units, each respective data storage unit configured to store a respective data bit of a data word. Stored data value parity generation circuitry is configured to generate a parity bit for the data word in dependence on the data bits of the data word stored in the plurality of data storage units. The stored data value parity generation circuitry is configured such that switching within the stored data value parity generation circuitry does not occur when the data word is read out from the plurality of data storage units. Transition detection circuitry is configured to detect a change in value of the parity bit.

A variety of applications can include apparatus and/or methods that provide parity data protection to data in a memory system for a limited period of time and not stored as permanent parity data in a non-volatile memory. Parity data can be accumulated in a volatile memory for data programmed via a group of access lies having a specified number of access lines in the group. A read verify can be issued to selected pages after programming finishes at the end of programming via the access lines of the group. With the programming of the data determined to be acceptable at the end of programming via the last of the access lines of the group, the parity data in the volatile memory can be discarded and accumulation can begin for a next group having a specified number of access lines. Additional apparatus, systems, and methods are disclosed.

A system is provided for performing error correction in memory. During operation, the system can receive a memory access request from a host processor. The system can then compare a memory address specified in the memory access request with a set of entries in an error correction code (ECC) mapping table. In response to the system determining that the memory address corresponds to at least one entry in the ECC mapping table, the system may determine, based on value in the counter field, whether the memory address belongs to a first portion or a second portion of the address range specified in the ECC mapping table entry. The system can then select a current ECC mode when the memory address belongs to the first portion; and select a previous ECC mode when the memory address belongs to the second portion. The system may then process the memory access request based on the selected ECC mode.

A method and a hardware accelerator device are provided for performing erasure coding on the hardware accelerator device that includes a dedicated buffer memory that is resident on the hardware accelerator device and that is connected to a second device via a bus, the method includes receiving, at the dedicated buffer memory, write data directly from the second device via the bus such that receiving the data at the dedicated buffer memory bypasses a buffer memory connected to a central processing unit (CPU), performing, at the hardware accelerator, an erasure coding operation on the write data received at the dedicated buffer memory to generate parity data based on the received write data, transmitting the parity data directly to a storage device connected to the hardware accelerator device via the bus such that transmitting the parity data bypasses the buffer memory connected to the CPU.

Disclosed in some examples are methods, systems, devices, and machine-readable mediums that provide for techniques for scrambling and/or updating meta-data that enable an efficient internal copyback operation. In some examples, in order to update the meta-data, the meta-data and host-data are separated and the only the meta-data is sent to the controller to be updated during a modified internal copyback operation. The host-data is not transmitted to the controller. While sending the meta-data utilizes resources of the communication link between the memory dies and the controller, it uses much fewer resources than if the host-data were also transmitted.

Apparatuses, systems, and methods for error correction. A memory device may have a number of memory cells each of which stores a bit of information. One or more error correction code (ECC) may be used to determine if the bits of information contain any errors. To mitigate the effects of failures of adjacent memory cells, the information may be divided into a first group and a second group, where each group contains information from memory cells which are non-adjacent to other memory cells of that group. Each group of information may include data bits and parity bits used to correct those data bits. For example, as part of a read operation, a first ECC circuit may receive information from even numbered memory cells, while a second ECC circuit may receive information from odd numbered memory cells.

A memory controller generates error codes associates with write data and a write address and provides the error codes over a dedicated error detection code link to a memory device during a write operation. The memory device performs error detection, and in some cases correction, on the received write data and write address based on the error codes. If no uncorrectable errors are detected, the memory device furthermore stores the error codes in association with the write data. On a read operation, the memory device outputs the error codes over the error detection code link to the memory controller together with the read data. The memory controller performs error detection, and in some cases correction, on the received read data based on the error codes.

Disclosed in some examples are methods, systems, devices, and machine-readable mediums that provide for techniques for scrambling and/or updating meta-data that enable an efficient internal copyback operation. In some examples, in order to update the meta-data, the meta-data and host-data are separated and the only the meta-data is sent to the controller to be updated during a modified internal copyback operation. The host-data is not transmitted to the controller. While sending the meta-data utilizes resources of the communication link between the memory dies and the controller, it uses much fewer resources than if the host-data were also transmitted.

An error correction circuit includes a memory that stores at least one decoding parameter, a low density parity check (LDPC) decoder that includes a first variable node storing one bit of the data, receives the at least one decoding parameter from the memory, decides a degree of the first variable node based on the at least one decoding parameter, and decides a decoding rule necessary for decoding of the one bit based on the degree of the first variable node, and an adaptive decoding controller that outputs corrected data based on a decoding result of the LDPC decoder.

A memory controller generates error codes associates with write data and a write address and provides the error codes over a dedicated error detection code link to a memory device during a write operation. The memory device performs error detection, and in some cases correction, on the received write data and write address based on the error codes. If no uncorrectable errors are detected, the memory device furthermore stores the error codes in association with the write data. On a read operation, the memory device outputs the error codes over the error detection code link to the memory controller together with the read data. The memory controller performs error detection, and in some cases correction, on the received read data based on the error codes.