Reliability of Physical Unclonable Function under Temperature and Supply Voltage Variations

Abstract

Physically Unclonable Function (PUF) has emerged as a cost-effective building block for crypto cores and security system. The unique signature of a PUF is primarily attributed to the process variations where the effects of other factors such as supply voltage, temperature and aging are considered to be minor. In this work, detail analysis to evaluate supply voltage and temperature effects on PUF reliability is presented. It is shown that the effects of supply voltage and temperature variations on PUF reliability can be comparable to the effects of process variations. It is also shown how temperature variation affects propagation delay of logic cells and consequently undermines PUF reliability. Simulation results using CMOS $0.18\mu \mathrm{m}$ technology in Cadence environment with $\pm 10\%$ power supply variations for a temperature range of-400C to $+70^{0}\mathrm{C}$ indicate that these effects can reduce PUF reliability by more than 58%.