Use soft-decision error-correction codes in Phase-Change Memory

Researches indicate that the resistance of phase-change material will become larger over the time. Use time-aware based soft-decision error correction code, which needs LLR to decode, can correct the errors in multilevel PCM effectively. Accurate LLR needs to read the resistance accurately, which will lead to a longer transmission latency. In this paper, we proposed a non-uniform correction strategy, which can reduce the read levels maintaining bit-error-rate performance. We use LDPC in correction of 4-level per cell PCM, and get the result via computer simulation.