Weebit - 2022 and beyond, page-1976

16 Sept 2022
28nm getting a workout with SKy130nm opensource PDK

28nm Weebit Nano Ltd #RRAM based #InMemoryComputing for similarity search application applied to a very interesting case of hyperspectral image classification! thanks to Amir Regev & folks at CEA-Leti



Abstract:
In this work, we propose a fully-binarized XOR-based IMSS (In-Memory Similarity Search) using RRAM (Resistive Random Access Memory) arrays. XOR (Exclusive OR) operation is realized using 2T-2R bitcells arranged along the column in an array. This enables simultaneous match operation across multiple stored data vectors by performing analog column-wise XOR operation and summation to compute HD (Hamming Distance).
The proposed scheme is experimentally validated on fabricated RRAM arrays. Full-system validation is performed through SPICE simulations using open source Skywater 130 nm CMOS PDK demonstrating energy of 17 fJ per XOR operation using the proposed bitcell with a full-system power dissipation of 145 μW. Using projected estimations at advanced nodes (28 nm) energy savings of ≈1.5× compared to the state-of-the-art can be observed for a fixed workload. Application-level validation is performed on HSI (Hyper-Spectral Image) pixel classification task using the Salinas dataset demonstrating an accuracy of 91%.

Fully-Binarized, Parallel, RRAM-based Computing Primitive for In-Memory Similarity Search | IEEE Journals & Magazine | IEEE Xplore