Improving Lifetime in MLC Phase Change Memory Using Slow Writes

This paper reports the performance and endurance impacts of a slow-write approach for a multi-level cell (MLC) of phase change memory (PCM). An MLC improves the density of PCM, but the endurance is a critical issue. To extend the lifetime of the cell, a slow-write approach is one of the techniques that is used. However, the slow-write approach increases the program execution time because it takes a long time. In this paper, we discuss three types of slow-write approach for MLC and evaluate the endurance and performance quantitatively to understand the effectiveness of our approach. Our evaluation results show that one of the approaches enhances the endurance of MLC PCM 1.57 times with a 1.41 % performance degradation on average compared with the conventional write operation.