A Joint Sensing and Decoding for Improving the Hard-Decision Lifetime of NAND Flash Memories
Seokju Han, Inayat Ali, Jeongseok Ha · 한국통신학회논문지 · 2024
Soft-decision decoding schemes are utilized for high data reliability of NAND flash memories. However, it requires excessive latency and power consumption compared to hard-decision (HD) decoding schemes. This work proposes a novel joint sensing and decoding scheme to extend the HD decoding lifetime. When the HD decoding fails, the proposed scheme re-reads HD channel outputs and judiciously combines the two consecutive HD readings utilizing reliability information from the failed HD decoding. Since the random telegraph noises impairing HD readings are statistically independent, the combining provides a diversity gain. Numerical results show that the proposed scheme significantly improves the HD lifetime.