VLSI Implementation of digital frequency sensors as hardware countermeasure

Non-invasive attacks are considered among the more serious threats for the hardware security due to there not exist evidences of them. Among these attacks, the clock glitch attack is one of the easier implementations. The typical countermeasure in front of this attack is a frequency sensor. In this paper, a VLSI design of a frequency digital sensor is presented. The simulation results, in a 0.35um standard CMOS technology, show a minimum timing resolution of 1.91ns and a minimum allowed period of 6.8ns. Finally, this implementation has been compared with an analog solution. The digital solution improves to the analog solution in timing resolution, power consumption, area consumption and propagation delay.