Countermeasures against physical security attacks on ICs utilizing on-chip wideband ADCs

Cryptographic ICs on edge devices for internet-of-things (IoT) applications are exposed to an adversary and threatened by malicious side channel analysis. On-chip analog monitoring by sensor circuits embedded inside the chips is one of the possible countermeasures against such attacks. An on-chip monitor circuit consisting of a successive approximation register (SAR) analog-to-digital converter (ADC) and an input buffer acquires a wideband signal, which enables to detects an irregular noise due to an active fault injection and a passive side channel leakage analysis. In this paper, several countermeasures against security attacks utilizing wideband on-chip monitors are reviewed. Each technique is implemented on a prototype chip, and the measurement results prove they can effectively detect and diagnose the security attacks.