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Computing‐in‐memory (CIM) is considered a feasible solution to the acceleration of multiply‐accumulate (MAC) operations at low power. The key to CIM is parallel MAC operations in the memory domain, and thus reductions in power consumption and memory‐access latency. Resistive random access memory (RRAM) can be a good candidate for the memory for CIM given its data nonvolatility, high data density, low‐latency read‐out, multilevel representation, and inherent current accumulation capability. Particularly, the last two attributes offer analog MAC operations in parallel in the memory domain. However, the fully analog MAC operation scheme causes significant power and area overheads for its peripheral circuits, particularly, analog‐to‐digital converters. To compensate for these downsides using digital processing, a method for sub‐array‐wise partial MAC operations over weight‐resistors that are optimally split to minimize power and area overheads for the peripheral circuits is proposed. The simulations performed highlight the optimal sub‐array of 4×w/2 in size. That is, weight‐splitting such that a single w‐bit weight is represented by w/2 RRAM cells, i.e., 2‐bit for each cell. For 8‐bit weights, the figure of merit (FOM) for this optimal case reaches ≈28.3× FOM for the case of no weight‐splitting. [ABSTRACT FROM AUTHOR]

Emerging non-volatile reduction-oxidation (redox)-based resistive switching memories (ReRAMs) exhibit a unique set of characteristics that make them promising candidates for the next generation of low-cost, low-power, tiny, and secure physical unclonable functions (PUFs). Their underlying stochastic ionic conduction behavior, intrinsic nonlinear current-voltage characteristics, and their well-known nano-fabrication process variability might normally be considered disadvantageous ReRAM features. However, using a combination of a novel architecture and special peripheral circuitry, this paper exploits these non-idealities in a physical one-way function, nonlinear resistive PUF, potentially applicable to a variety of cyber-physical security applications. We experimentally verify the performance of valency change mechanism (VCM)-based ReRAM in nano-fabricated crossbar arrays across multiple dies and runs. In addition to supporting a massive pool of challenge-response pairs (CRPs), using a combination of experiment and simulation our proposed PUF exhibits a reliability of 98.67%, a uniqueness of 49.85%, a diffuseness of 49.86%, a uniformity of 47.28%, and a bit-aliasing of 47.48%. [ABSTRACT FROM PUBLISHER]