A fully-digital EM pulse detector

ElectroMagnetic Pulse Injection (EMPI) has recently been demonstrated to be an efficient fault injection technique with many advantages especially when considering security issues of Systems on Chip (SoC) embedded on ball grid array packages, i.e. when adversaries do not have an easy access to the backside. EMPI must therefore be considered as a real threat against smartcards and SoC from now on. Among the usual countermeasures against fault attacks, one can identify the use of embedded sensors. If one can find voltage glitch or laser shot detectors in the literature, there is only one proposal which puts forward the idea of detecting ElectroMagnetic Pulse (EMP). However, this former sensor requires a fine tuning of some timing characteristics and, as a result, its use appears complex and even impractical within a SoC which are heterogeneous by nature and designed by worldwide teams. Within this context, this paper introduces and experimentally validates a new sensor allowing to detect EMP. Because the sensor is fully digital, it is low cost and above all fully compliant with the standard design flow of SoC.