Flexible self-rectifying synapse array for energy-efficient edge multiplication in electrocardiogram diagnosis
Younghyun Lee, Hakseung Rhee, Geunyoung Kim, Woon Hyung Cheong, Do Hoon Kim, Hanchan Song, Sooyeon Narie Kay, Jongwon Lee, Kyung Min Kim
Abstract
Edge computing devices, which generate, collect, process, and analyze data near the source, enhance the data processing efficiency and improve the responsiveness in real-time applications or unstable network environments. To be utilized in wearable and skin-attached electronics, these edge devices must be compact, energy efficient for use in low-power environments, and fabricable on soft substrates. Here, we propose a flexible memristive dot product engine (f-MDPE) designed for edge use and demonstrate its feasibility in a real-time electrocardiogram (ECG) monitoring system. The f-MDPE comprises a 32 × 32 crossbar array embodying a low-temperature processed self-rectifying charge trap memristor on a flexible polyimide substrate and exhibits high uniformity and robust electrical and mechanical stability even under 5-mm bending conditions. Then, we design a neural network training algorithm through hardware-aware approaches and conduct real-time edge ECG diagnosis. This approach achieved an ECG classification accuracy of 93.5%, while consuming only 0.3% of the energy compared to digital approaches, highlighting the strong potential of this approach for emerging edge neuromorphic hardware. Edge computing devices must be compact and energy efficient for use in low-power environments. Here, the authors propose a flexible memristive dot product engine designed for edge use with 0.3% energy consumption compared to digital approaches.