 Image Number 10 for United States Patent #8116141.
A distribution analyzing method for a nonvolatile memory device having memory cells exhibiting overlapping first and second threshold voltage distributions includes; detecting a degree of overlap between the first and second threshold voltage distributions by reading data stored in the memory cells and determining read index data from the read data, and estimating a distribution characteristic for at least one of the overlapping threshold voltage distributions using the read index data.
|