Analog computation-in-memory (CIM) architecture alleviates massive data movement between the memory and the processor, thus promising great prospects to accelerate certain computational tasks in an energy-efficient manner. However, data converters involved in these architectures typically achieve the required computing accuracy at the expense of high area and energy footprint which can potentially determine CIM candidacy for low-power and compact edge-AI devices. In this work, we present a memory-periphery co-design to perform accurate A/D conversions of analog matrix-vector-multiplication (MVM) outputs. Here, we introduce a scheme where select-lines and bit-lines in the memory are virtually fixed to improve conversion accuracy and aid a ring-oscillator-based A/D conversion, equipped with component sharing and inter-matching of the reference blocks. In addition, we deploy a self-timed technique to further ensure high robustness addressing global design and cycle-to-cycle variations. Based on measurement results of a 4Kb CIM chip prototype equipped with TSMC 40nm, a relative accuracy of up to 99.71% is achieved with an energy efficiency of 115.1 TOPS/W and computational density of 12.1 TOPS/mm2 for the MNIST dataset. Thus, an improvement of up to 11.3X and 7.5X compared to the state-of-the-art, respectively.

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Memristor technology is a promising alternative to CMOS due to its high integration density, near-zero standby power, and ability to implement novel resistive computing. One of the major limitations of these architectures is the limited endurance of memristor devices, especially when a logic gate requires multiple steps/switching to execute the logic operations. To alleviate the endurance requirement and improve the performance, we present a novel logic design style, called scouting logic that executes any logic gate by only reading the memristor devices and without changing their states. Hence, no impact on the memristors' endurance. The proposed design is implemented using two styles (current and voltage based). To illustrate the performance of scouting logic based designs, the area, delay, and power consumption are analyzed and compared with state-ofthe- art. The results show that scouting logic improves the delay and power consumption by at least a factor of 2.3, while having similar or less area overhead. Finally, we discuss the potential applications and challenges of scouting logic.@en