Skewed Straintronic Magnetotunneling-Junction-Based Ternary Content-Addressable Memory—Part II

Abstract

Part I of this paper discussed the design of a four-terminal skewed straintronic magnetotunneling junction (ss-MTJ) switch, and its adaptation to a non-Boolean “one transistor, one trench capacitor, and one ss-MTJ” ternary content-addressable memory (TCAM) cell. This part of the paper discusses a TCAM array based on ss-MTJ-TCAM cells and the associated peripherals for search operation. We show that non-Boolean associative processing of the ss-MTJ-TCAM cells enhances energy-efficiency and performance of an ss-MTJ-based TCAM array. The energy-delay-product (EDP) of ss-MTJ-based TCAM is compared against CMOS-based TCAM for a 144 × 256 array. The minimum EDP in ss-MTJ-based TCAM is ~10.8× lower than the minimum EDP in CMOS-based TCAM. Additionally, the operational frequency at which the ss-MTJ-based design shows the minimum EDP is ~9.4× higher than the respective frequency in the CMOS-based design. We also compare ss-MTJ-based TCAM against other state-of-the-art MTJ-based TCAMs. The comparison shows that the ss-MTJ-based TCAM also outperforms MTJ-based TCAMs in cell density, search delay, and search energy. Finally, we discuss implications of process variability in ss-MTJ to TCAM implementation and identify critical design parameters in ss-MTJ-based TCAM to enhance its robustness and area/ energy-efficiency.