Novel In-Memory Matrix-Matrix Multiplication with Resistive Cross-Point Arrays

Resistive cross-point array can be used to implement vector-matrix multiplication in analog fashion. However, the output is in the form of analog current, and thus requires A/D conversion prior to digital storage. This paper develops and demonstrates a novel in-memory matrix-matrix multiplication method (M2M) that can compute and store the result directly inside the memory itself without requiring A/D conversion. Compared with the conventional approach, M2M provides >10 × improvement in energy and area efficiency, and another 2 orders improvement when matrices are low-rank and sparse.