Towards data reliable crossbar-based memristive memories

A series of breakthroughs in memristive devices have demonstrated the potential of using crossbar-based memristor arrays as ultra-high-density and low-power memory. However, their unique device characteristics could cause data disturbance for both read and write operations resulting in serious data reliability problems. This paper discusses such reliability issues in detail and proposes a comprehensive yet low area-/performance-/energy-overhead solution addressing these problems. The proposed solution applies asymmetric voltages for disturbance confinement, inserts redundancy for disturbance detection, and employs a refreshing mechanism to restore weakened data. The results of a case study show that the average overheads of area, performance and energy consumption for achieving data reliability, over a baseline unreliable memory system, are 3%, 4%, and 19% respectively.