Although offering great potential for energy-efficient edge-AI, memristor-based CIM accelerators are severely hindered by IR drop induced errors. To tackle this, we propose a low-cost mitigation technique by first quantifying the impact of IR drop on the accuracy. Then, a mitigation strategy is developed to compensate for IR drop-induced inference accuracy reduction by combining an optimized mapping scheme with a fine-tuned calibration of the ADC. Results show the proposed solution can effectively mitigate IR drop with a negligible overhead.

RRAM-based compute-in-memory (CIM) AI accelerators integrate memory cells with mixed-signal peripherals to enable energy-efficient, low-latency edge computing. These architectures require novel test techniques for unique electrical defects. Current system-level functional tests cannot guarantee defect-free circuits, while accurate circuit-level techniques remain non-scalable to Deep Neural Networks (DNNs). To bridge this gap, we present the first structural test methodology for CIM DNNs, unifying system-level analysis with circuit-level precision. We accurately model RRAM crossbar defects to formulate test patterns, and then propagate results across layers for comprehensive structural testing. Generated test patterns are optimized either for 96% defect coverage or test time reduction by a factor of three while covering all unique defects and maintaining over 73% defect strength coverage.

Edge AI accelerators have revolutionized intelligent information processing, enabling applications, such as self-driving cars and low-power IoT devices. Design efforts prioritize computational power and energy efficiency. Nevertheless, testability is also critical for in-field, reliable operation, especially for novel architectures such as memristive, analog Computation-in-Memory (CIM) cores. These structures combine emerging Resistive Random Access Memory (RRAM) with CMOS peripherals to efficiently implement vector-matrix-multiplication (VMM) operations for inference. Current research on AI Accelerator testing relies on functional test patterns, derived from abstract and unrealistic fault models. This paper presents a novel structural testing methodology for CIM VMM circuits. The methodology utilizes device-level defect models and defines new fault models for CIM VMM. The resulting test patterns are optimized to maximize defect coverage and minimize test time, since they require only a single write operation per victim cell.