Memory operating method for increasing cell capacity based on resistance characteristic of memory and associated memory device

摘要

A memory operating method comprises the following steps: a first read voltage is applied to the memory cell to read a first group of data levels of the memory cell; and if the data of the memory cell can not be read with the first read voltage, a second read voltage is applied to the memory cell to read a second group of data levels of the memory cell.

主权项

1. A memory operating method, comprising:
applying a first read voltage to a memory cell having a plurality of resistance levels, wherein the memory cell is a multi-level-cell of a phase change memory; and applying a second read voltage to the memory cell when failing to read data of the memory cell under the first read voltage; wherein the second read voltage is set to larger than the first read voltage when a resistance of the memory cell under the first read voltage is larger than an upper resistance limit of a resistance sensing window; and the second read voltage is set to smaller than the first read voltage when the resistance value of the memory cell under the first read voltage is smaller than a lower resistance limit of the resistance sensing window; wherein the resistance sensing window has the upper resistance limit and the lower resistance limit between which data corresponding to a resistance level exhibited by the memory cell is configured to be read.