| Patent application number | Description | Published |
|---|
| 20080215798 | Randomizing for suppressing errors in a flash memory - Original data to be stored in a nonvolatile memory are first randomized while preserving the size of the original data, In response for a request for the original data, the randomized data are retrieved, derandomized and exported without authenticating the requesting entity. ECC encoding is applied either before or after randomizing; correspondingly, ECC decoding is applied either after or before derandomizing. | 09-04-2008 |
| 20080263265 | ADAPTIVE DYNAMIC READING OF FLASH MEMORIES - Each of a plurality of flash memory cells is programmed to a respective one of L≧2 threshold voltage states within a threshold voltage window. Values of parameters of threshold voltage functions are adjusted in accordance with comparisons of the threshold voltages of some or all of the cells to two or more of m≧2 threshold voltage intervals within the threshold voltage window. Reference voltages for reading the cells are selected based on the values. Alternatively, the m threshold voltage intervals span the threshold voltage window, and respective threshold voltage states are assigned to the cells based on numbers of cells whose threshold voltages are in the intervals, without re-reading the cells. | 10-23-2008 |
| 20080263266 | ADAPTIVE DYNAMIC READING OF FLASH MEMORIES - Each of a plurality of flash memory cells is programmed to a respective one of L≧2 threshold voltage states within a threshold voltage window. A histogram is constructed by determining how many of some or all of the cells have threshold voltages in each of two or more of m≧2 threshold voltage intervals within the threshold voltage window. Reference voltages for reading the cells are selected based on estimated values of shape parameters of the histogram. Alternatively, the cells are read relative to reference voltages that define m≧2 threshold voltage intervals that span the threshold voltage window, to determine numbers of at least a portion of the cells whose threshold voltages are in each of two or more of the threshold voltage intervals. Respective threshold voltage states are assigned to the cells based on the numbers without re-reading the cells. | 10-23-2008 |
| 20080291724 | MULTI-BIT-PER-CELL FLASH MEMORY DEVICE WITH NON-BIJECTIVE MAPPING - To store a plurality of input bits, the bits are mapped to a corresponding programmed state of one or more memory cells and the cell(s) is/are programmed to that corresponding programmed state. The mapping may be many-to-one or may be an “into” generalized Gray mapping. The cell(s) is/are read to provide a read state value that is transformed into a plurality of output bits, for example by maximum likelihood decoding or by mapping the read state value into a plurality of soft bits and then decoding the soft bits. | 11-27-2008 |
| 20080294960 | MEMORY-EFFICIENT LDPC DECODING - To decode a representation of a codeword that encodes K information bits as N>K codeword bits, messages are exchanged between N bit nodes and N−K check nodes of a graph in which E edges connect the bit nodes and the check nodes. While messages are exchanged, fewer than E of the messages are stored, and/or fewer than N soft estimates of the codeword bits are stored. In some embodiments, the messages are exchanged only within sub-graphs and between the sub-graphs and one or more external check nodes. While messages are exchanged, the largest number of stored messages is the number of edges in the sub-graph with the most edges plus the number of edges that connect the sub-graphs to the external check node(s), and/or the largest number of stored soft estimates is the number of bit nodes in the sub-graph with the most bit nodes. | 11-27-2008 |
| 20090080259 | Post-Facto Correction For Cross Coupling In A Flash Memory - A method of storing and reading data, using a memory that includes a plurality of cells (e.g. flash cells), such that data are stored in the cells by setting respective values of a physical parameter of the cells (e.g. threshold voltage) to be indicative of the data, and such that data are read from the cells by measuring those values. One of the cells and its neighbors are read. The data stored in the cell are estimated, based on the measurements and on respective extents to which the neighbors disturb the reading. Preferably, the method also includes determining those respective extents to which the neighbors disturb the reading, for example based on the measurements themselves. | 03-26-2009 |
| 20090217124 | METHOD AND DEVICE FOR MULTI PHASE ERROR-CORRECTION - Data bits to be encoded are split into a plurality of subgroups. Each subgroup is encoded separately to generate a corresponding codeword. Selected subsets are removed from the corresponding codewords, leaving behind shortened codewords, and are many-to-one transformed to condensed bits. The final codeword is a combination of the shortened codewords and the condensed bits. A representation of the final codeword is decoded by being partitioned to a selected subset and a plurality of remaining subsets. Each remaining subset is decoded separately. A subset whose decoding is terminated is decoded again, at least in part according to the selected subset. If the encoding and decoding are systematic then the selected subsets are of parity bits. | 08-27-2009 |
| 20100135074 | Post-Facto Correction for Cross Coupling in a Flash Memory - A method of storing and reading data, using a memory that includes a plurality of cells (e.g. flash cells), such that data are stored in the cells by setting respective values of a physical parameter of the cells (e.g. threshold voltage) to be indicative of the data, and such that data are read from the cells by measuring those values. One of the cells and its neighbors are read. The data stored in the cell are estimated, based on the measurements and on respective extents to which the neighbors disturb the reading. Preferably, the method also includes determining those respective extents to which the neighbors disturb the reading, for example based on the measurements themselves. | 06-03-2010 |
| 20110134692 | ADAPTIVE DYNAMIC READING OF FLASH MEMORIES - A data storage device includes a controller and storage elements. The controller is configured to read a threshold voltage of each of a plurality of the storage elements to generate read threshold data and to assign reference voltages defining each of a plurality of voltage threshold states based on the read threshold data. | 06-09-2011 |
