Locking by Untuning: A Lock-Less Approach for Analog and Mixed-Signal IC Security

Mohamed Elshamy (1) , Alhassan Sayed (1) , Marie-Minerve Louërat (1) , Hassan Aboushady (1) , Haralampos-G. Stratigopoulos (1)

1 CIAN - Circuits Intégrés Numériques et Analogiques

We propose an anti-piracy security approach for programmable analog and mixed-signal (AMS) Integrated Circuits (ICs). The security approach relies on functionality locking by leveraging the inherent programmability and utilizing the configuration settings as secret keys or, equivalently, the programming bits as key-bits. When invalid keys are applied, the circuit is untuned and, as a result, its functionality breaks, i.e., at least one of the performances violates its specification. As long as the calibration algorithm that produces the configuration settings can be kept secret, the proposed approach can serve as a countermeasure against all types of counterfeiting, i.e., cloning, overbuilding, remarking, and recycling. An important advantage of the proposed approach is that it is lock-less. It leaves the design intact, there is no change to the design flow, and there is no performance penalty and no area or power overheads due to the lock operation. We demonstrate it on a Σ∆ Analogto-Digital Converter (ADC) with 194-bit programmability and complex calibration algorithm used in the context of highlydigitized, multi-standard RF receivers.

Domaines: Micro et nanotechnologies/Microélectronique; Cryptographie et sécurité [cs.CR]

Mohamed Elshamy, Alhassan Sayed, Marie-Minerve Louërat, Hassan Aboushady, Haralampos-G. Stratigopoulos. Locking by Untuning: A Lock-Less Approach for Analog and Mixed-Signal IC Security. IEEE Transactions on Very Large Scale Integration (VLSI) Systems, 2021, 29 (12), pp.2130-2142. ⟨10.1109/TVLSI.2021.3117584⟩. ⟨hal-03361417⟩