Adaptive Generation of Unique IDs for Digital Chips through Analog Excitation

Globalization of the integrated circuit design and manufacturing flow has successfully ameliorated design complexity and fabrication cost challenges, and helped deliver cost-effective products while meeting stringent time-to-market requirements. On the flip side, it has resulted in various forms of security vulnerabilities in the supply chain that involves designers, fabs, test facilities, and distributors until the end-product reaches customers. One of the biggest threats to semiconductor industry today is the entry of aged, reject, or cloned parts, that is, counterfeit chips, into the supply chain, leading to annual revenue losses in the order of billions of dollars. While traceability of chips between trusted parties can help monitor the supply chain at various points in the flow, existing solutions are in the form of integrating costly hardware units on chip, or utilizing easy-to-circumvent inspection-based detection techniques. In this article, we propose a technique for adaptive unique ID generation that leverages process variations, enabling chip traceability. The proposed method stimulates digital chips with an analog signal from the supply lines, which serve as primary inputs to each gate in the signal path. Using a sinusoidal signal that exercises the transistors as gain components, we create a chip-specific response that can be post-processed into a digital ID. The proposed technique enables quick and cost-effective authenticity validation that requires no on-chip hardware support. Our simulation and experimentation on actual chips show that the proposed technique is capable of generating unique IDs even in the presence of environmental noise.