Design Limitations in Oxide-Based Memristive Ternary Content Addressable Memories

Abstract

Memristive devices offer energy and area efficient non-volatile data storage for data-intense Ternary Content Ad-dressable Memory (TCAM) architectures. However, depending on the storage implementation in the bitcell design, the matching functionality shows multiple undesired discharge effects leading to false look-up results. In particular, the ternary storage suffers during the look-up operation from a poor resistance ratio, match-line leakage and device variabilities. In this paper, we investigate the inherent, design-dependent limitations in the ternary state storage capability due to different memristive TCAM bitcell design parameters and device variabilities. We test these limits based on variability-aware device simulations and isolate crucial parameters for the optimization of memristive TCAMs.