Implications of Distributed On-Chip Power Delivery on EM Side-Channel Attacks

EM side-channel leakage is typically the derivative of the power consumption profile of a circuit. Since the fluctuations of the supply voltage strongly depend on the topology and characteristics of the power distribution network (PDN), the design of the PDN has a direct impact on the EM side-channel leakage signature. In this paper, the security implications of distributed on-chip voltage regulators against EM side-channel attacks are investigated. Extensive HFSS simulations have demonstrated that the maximum EM radiation can be reduced by 33 dB and 11 dB, respectively, at the front and back sides of an integrated circuit with distributed on-chip voltage regulation since the power is delivered locally through partially shorter and thinner metal lines as compared to the designs with offchip voltage regulators.