System, method and computer readable medium for generating soft information

摘要

A system, a method and a non-transitory computer readable medium for generating soft information. The method may include performing a first set of read attempts of flash memory cells using a first set of read thresholds to provide first read results; calculating for each flash memory cell in response to the first read results, first cell information indicative of a first change-inducing read threshold; performing a second set of read attempts of the flash memory cells using a second set of read thresholds to provide second read results, calculating for each flash memory cell in response to the second read results, second cell information indicative of a second change-inducing read threshold; and generating, for each flash memory cell soft information in response to the first cell information and the second cell information of the flash memory cell.

主权项

1. A method for generating soft information, the method comprising: performing by a flash memory controller a first set of read attempts of flash memory cells using a first set of read thresholds to provide first read results; calculating, by the flash memory controller, for each flash memory cell of the flash memory cells and in response to the first read results, first cell information indicative of a first change-inducing read threshold; performing by the flash memory controller a second set of read attempts of the flash memory cells using a second set of read thresholds to provide second read results; wherein at least one read threshold of the second set of read thresholds substantially equals at least one read threshold of the first set of read thresholds; calculating, by the flash memory controller, for each flash memory cell of the flash memory cells and in response to the second read results, second cell information indicative of a second change-inducing read threshold; and generating, for each flash memory cell of the flash memory cells, soft information in response to the first cell information and the second cell information of the flash memory cell;
wherein the first set of read thresholds virtually partitions a threshold voltage distribution of the flash memory cells to multiple first voltage ranges; and wherein the second set of read thresholds virtually partitions the threshold voltage distribution of the flash memory cells to multiple second voltage ranges.