NONVOLATILE MEMORY AND DATA WRITING METHOD

摘要

According to one embodiment, a nonvolatile memory includes a memory cell array having a plurality of memory cells configured to store 3-bit data corresponding to first to third pages. Data coding, in which first page data values have one boundary, and second and three page data values each have three boundaries, is used to perform a first stage program based on data written into first page d, a second stage program based on data written into the first, second, and third pages, and a third stage program based on data written into the first, second, and third pages.

主权项

1. A nonvolatile memory comprising:
a memory cell array having a plurality of memory cells configured to store 3-bit data corresponding to first to eighth threshold regions, the 3-bit data corresponding to first to third pages, respectively; and a control unit configured to:
perform a first stage program on the memory cell based on data written to the first page;perform a second stage program on the memory cell based on data written to the first, second, and third pages after the first stage program; andperform a third stage program on the memory cell based on data written to the first, second, and third pages after the second stage program, the first to third stage programs being performed using data coding of the memory cells having one boundary with different bit values for the first page among seven boundaries between adjacent threshold regions, having three boundaries with different bit values for the second page among the seven boundaries, and having three boundaries with different bit values for the third page among the seven boundaries.