Passive Lightweight On-chip Sensors for Power Side Channel Attack Detection

Hardware implementations of encryption engines are susceptible to Power Side Channel Attacks (PSCA) and countermeasures only make attacks harder without eliminating them. This work presents a temperature tolerant 65nm CMOS passive on-chip PSCA detection sensor for a AES-128 engine. The design uses on-chip sub-threshold oscillator to detect the resistor normally placed by an attacker on the power-line of an AES chip to mount PSCA. The measurement demonstrates 99.9% probability of successful detection, 1.1ms detection time, minimal area overhead compared to the encryption area and 0.83mW power.