Comparison of bi-stable and delay-based Physical Unclonable Functions from measurements in 65nm bulk CMOS

Physical Unclonable Functions (PUFs) are security primitives used in a number of security applications like authentication, identification, and secure key generation. PUF implementations are evaluated on their security characteristics (uniqueness, randomness, and reliability), as well as conventional VLSI design metrics (area, power, and performance). We compare bi-stable based PUFs (SRAM and sense amplifiers) and delay based PUFs (arbiter and ring oscillator) using measurements from a testchip in 65nm bulk CMOS. Security metrics are measured on multiple dies and reliability measurements are based on multiple evaluations of PUF circuits across operating voltage (1.0V to 1.4V) and temperature (-20°C to 85°C).