Writing without disturb on phase change memories by integrating coding and layout design
We integrate coding techniques and layout design to elimi- nate write-disturb in phase change memories (PCMs), while enhancing lifetime and host-visible capacity. We first pro- pose a checkerboard confguration for cell layout to elimi- nate write-disturb while doubling the memory lifetime. We then introduce two methods to jointly design Write-Once- Memory (WOM) codes and layout. The first WOM-layout design improves the lifetime by more than double without compromising the host-visible capacity. The second design applies WOM codes to even more dense layouts to achieve both lifetime and capacity gains. The constructions demon- strate that substantial improvements to lifetime and host- visible capacity are possible by co-designing coding and cell layout in PCM.