Nonvolatile Crossbar 2D2R TCAM with Cell Size of 16.3 F-2 and K-means Clustering for Power Reduction

Abstract

A 28nm 16Kb nonvolatile ternary content addressable memory (nvTCAM) test chip based on logic-compatible resistive memory (ReRAM) is demonstrated with high density and low power for packet routing in network applications. The crossbar array exhibits a smallest cell size of 16.3F(2) by using 2-diode-2-ReRAM (2D2R) nvTCAM cell, useful for further 3-dimension (3D) stacking. K-means clustering is employed to allocate the storage of routing table entry for given bank count. Then the search of destination IP address can be classified and confined to a specific bank, reducing active banks for power saving. Evaluations show >3X improvement in cell density and >70% reduction in search energy with limited overhead in silicon area for bank count of four.