| 摘要 |
Data bits are programmed in cells of a flash memory which is divided into a multiplicity of separately erasable physical blocks, which are in turn split into individual physical pages to which the data bits can be written. The data bits are held in multilevel cells that store one lower bit and one upper bit per cell. The four states of which are distinguished by three voltage threshold values. The lower states are associated with the lower bit and the upper states are associated with the upper bit. The pages are distinguished by lower pages allocated to the lower bits, and upper pages allocated to the upper bits. Lower and upper pages which contain the same cells are combined by a pairing table to form paired pages. Reliable storage of data bits is achieved by programming paired pages with the same data bits and listing them as reliable paired pages in management data for the flash memory. |
