Patent classifications
G11C29/00
Memory device capable of repairing defective word lines
The disclosure provides a memory device which includes a plurality of word lines grouped into a plurality of WL sets; and a plurality of redundant word lines grouped into M RWL sets; and a memory control circuit connected to the WL sets and the RWL sets and configured to replace a plurality of defective WL sets of the plurality WL sets by selecting from the RWL sets, wherein each of the plurality of defective WL sets comprises at least a defective word line, all of the M RWL sets are available for repairing the WL sets during a wafer stage, where M is an integer greater than 2, and N of M RWL sets is available for repairing the WL sets during the wafer stage, during a package stage and during a post package stage, where N is an integer less than M.
Method and Apparatus for Flexible RAID in SSD
A solid state drive (SSD) employing a redundant array of independent disks (RAID) scheme includes a flash memory chip, erasable blocks in the flash memory chip, and a flash controller. The erasable blocks are configured to store flash memory pages. The flash controller is operably coupled to the flash memory chip. The flash controller is also configured to organize certain of the flash memory pages into a RAID line group and to write RAID line group membership information to each of the flash memory pages in the RAID line group.
STORAGE SYSTEM AND INFORMATION PROCESSING SYSTEM FOR CONTROLLING NONVOLATILE MEMORY
According to one embodiment, a storage system includes a controller. The controller receives, from a host, a write command including a block address indicating a first block in a plurality of blocks, and a page address indicating a first page of the first block. The controller writes data designated by the write command to the first page of the first block. The controller notifies the host 2 of a page address indicating a latest readable page which is included in pages of the first block, the pages containing data which was written by the host before the designated data was written to the first page, the latest readable page having become readable by writing the designated data to the first page.
MEMORY DEVICES HAVING VARIABLE REPAIR UNITS THEREIN AND METHODS OF REPAIRING SAME
A memory device includes a row decoder, a column decoder, and a repair control circuit, which is configured to: (i) compare a row address with a stored failed row address, (ii) compare a column address with a stored failed column address, (iii) control the row decoder to activate the at least one of a plurality of redundancy word lines when the row address corresponds to the failed row address, and (iv) control the column decoder to activate at least one of a plurality of redundancy bit lines when the column address corresponds to the failed column address. The repair control circuit varies a repair unit according to an address input during a repair operation.
MEMORY REPAIR USING OPTIMIZED REDUNDANCY UTILIZATION
A semiconductor device is provided, which contains a memory bank including M primary word lines and R replacement word lines, a row/column decoder, and an array of redundancy fuse elements. A sorted primary failed bit count list is generated in a descending order for the bit fail counts per word line. A sorted replacement failed bit count list is generated in an ascending order of the M primary word lines in an ascending order. The primary word lines are replaced with the replacement word lines from top to bottom on the lists until a primary failed bit count equals a replacement failed bit count or until all of the replacement word lines are used up. Optionally, the sorted primary failed bit count list may be re-sorted in an ascending or descending order of the word line address prior to the replacement process.
Imprint management for memory
Methods, systems, and devices for imprint recovery management for memory systems are described. In some cases, memory cells may become imprinted, which may refer to conditions where a cell becomes predisposed toward storing one logic state over another, resistant to being written to a different logic state, or both. Imprinted memory cells may be recovered using a recovery or repair process that may be initiated according to various conditions, detections, or inferences. In some examples, a system may be configured to perform imprint recovery operations that are scaled or selected according to a characterized severity of imprint, an operational mode, environmental conditions, and other factors. Imprint management techniques may increase the robustness, accuracy, or efficiency with which a memory system, or components thereof, can operate in the presence of conditions associated with memory cell imprinting.
APPARATUSES AND METHODS FOR ZONE-BASED SOFT POST-PACKAGE REPAIR
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.
SELF-REPAIR FOR SEQUENTIAL SRAM
In some embodiments, a system comprises a static random access memory (SRAM) device and a controller. The SRAM device comprises a bit cell array comprising a plurality of bit cells arranged in a plurality of rows and a plurality of columns, each column operatively coupled to a pair of bit lines, wherein the plurality of columns is arranged as a plurality of column groups each comprising a plurality of local columns. The SRAM device further comprises a plurality of column decoders, each associated with a column group of the plurality of column groups. In some embodiments, the controller may be configured to read the local columns included in the column group by, for a given local column, sensing a voltage difference on a corresponding pair of bit lines, in a rearranged sequential order that is different from a physical sequential order of the plurality of local columns.
Redundancy analysis method and redundancy analysis apparatus
A redundancy analysis method of replacing a faulty part of a memory with at least one spare according to the present embodiment includes: acquiring fault information of the memory; and redundancy-allocating the fault with combinations of the spares to correspond to combination codes corresponding to the combinations of the spares, in which, the redundancy-allocating with the combination of the spare areas includes performing parallel processing on each combination of the spares.
Method for converting a floating gate non-volatile memory cell to a read-only memory cell and circuit structure thereof
According to principles as discussed herein, an EEPROM cell is provided and then, after testing the code, using the exact same architecture, transistors, memory cells, and layout, the EEPROM cell is converted to a read-only memory (“ROM”) cell. This conversion is done on the very same integrated circuit die using the same layout, design, and timing with only a single change in an upper level mask in the memory array. In one embodiment, the mask change is the via mask connecting metal 1 to poly. This allows the flexibility to store the programming code as non-volatile memory code, and then after it has been tested, at time selected by the customer, some or all of that code from a code that can be written to a read-only code that is stored in a ROM cell that is composed the same transistors and having the same layout.