A 32 nm 0.58-fJ/Bit/Search 1-GHz Ternary Content Addressable Memory Compiler Using Silicon-Aware Early-Predict Late-Correct Sensing With Embedded Deep-Trench Capacitor Noise Mitigation
Igor Arsovski, Travis Hebig, Daniel Dobson, Reid Wistort · IEEE Journal of Solid-State Circuits · 2013
A Ternary Content Addressable Memory (TCAM) uses a two-phase search operation where early prediction on its pre-search results prematurely activates the subsequent main-search operation, which is later interrupted only if the final pre-search results contradict the early prediction. This early main-search activation improves performance by 30%, while the low-probability of a late-correct has a negligible impact on power consumption. This Early-Predict Late-Correct (EPLC) sensing with silicon-aware tuning enables a high-performance TCAM compiler implemented in 32 nm High-K Metal Gate SOI process to achieve 1 Gsearch/sec throughput on a 2048×640 bit TCAM instance while consuming only 0.76 W, resulting in an energy efficiency of 0.58-fJ/bit/search. Embedded Deep-Trench (DT) capacitance reduces power supply collapse by 53% while adding only 5% area overhead for a total TCAM area of 1.56 mm2.