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The digital integrated circuit (IC) design industry is continuously evolving. However, the rapid advancements in technology are accompanied by major reliability concerns. Conventional clock-based synchronous designs become exceedingly susceptible to transient errors, caused by radiation rays, power jitters, electromagnetic interferences (EMIs), and/or other noise sources, primarily due to aggressive device and voltage scaling. quasi-delay-insensitive (QDI) asynchronous (clockless) circuits demonstrate inherent robustness against such transient errors, owing to their unique architecture. However, they are not completely immune. This article presents a hardened QDI Sleep Convention Logic (SCL) asynchronous architecture, which can fully recover from radiation-induced single-event effects such as single-event upset (SEU) and single-event latch-up (SEL). Multiple benchmark circuits are designed based on the proposed architecture. The simulation results indicate that the proposed designs offer substantial energy savings per operation, dissipate substantially less power during idle phases, and have lower area footprints in comparison to designs based on an existing resilient Null Convention Logic (NCL) architecture at the cost of increased latency. In addition, a formal verification framework for the proposed architecture is also presented. The performance and scalability of the proposed verification scheme are demonstrated using several multiplier benchmark circuits of varying width.
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Illegal Trojan design and detection in asynchronous NULL Convention Logic and Sleep Convention Logic circuits
Abstract With Cyber warfare, detection of hardware Trojans, malicious digital circuit components that can leak data and degrade performance, is an urgent issue. Quasi‐Delay Insensitive asynchronous digital circuits, such as NULL Convention Logic (NCL) and Sleep Convention Logic, also known as Multi‐Threshold NULL Convention Logic (MTNCL), have inherent security properties and resilience to large fluctuations in temperatures, which make them very alluring to extreme environment applications, such as space exploration, automotive, power industry etc. This paper shows how dual‐rail encoding used in NCL and MTNCL can be exploited to design Trojans, which would not be detected using existing methods. Generic threat models for Trojans are given. Formal verification methods that are capable of accurate detection of Trojans at the Register‐Transfer‐Level are also provided. The detection methods were tested by embedding Trojans in NCL and MTNCL Rivest‐Shamir‐Adleman (RSA) decryption circuits. The methods were applied to 25 NCL and 25 MTNCL RSA benchmarks of various data path width and provided 100% rate of detection.
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- Award ID(s):
- 1717420
- PAR ID:
- 10379874
- Publisher / Repository:
- DOI PREFIX: 10.1049
- Date Published:
- Journal Name:
- IET Computers & Digital Techniques
- Volume:
- 16
- Issue:
- 5-6
- ISSN:
- 1751-8601
- Format(s):
- Medium: X Size: p. 172-182
- Size(s):
- p. 172-182
- Sponsoring Org:
- National Science Foundation
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