Ultra-low power current-based PUF

In this paper, the first class of low power current-based physically unclonable functions (PUFs) is introduced. The new PUF circuit is able to convert the analog variations present in device leakage currents to a unique digital quantity at high speed and low power. Robust digital responses are achieved with the new architecture in presence of fluctuations in operational conditions such as temperature and supply voltage. The experimental results suggest 3% response error rate under extreme temperature variations from -55°C to 125°C and 20% fluctuations in supply voltage. The PUF consumes 150 μWatt for a duration of 250 ps per each response bit (37.5 femto joules of energy per response bit).