Testing Temperature-Dependent Resistors as Potential Physical Unclonable Functions

This work investigates the potential of temperature-dependent resistors to serve as Physical Unclonable Functions (PUFs). Five types of temperature-dependent resistors were subjected to testing at four different temperatures. The analysis of the collected data revealed patterns and trends that do not immediately qualify the devices as PUFs, but indicate their potential to be utilised for the realisation of unique responses based on them. In particular, by applying a binary discretisation technique, distinct behaviour profiles were identified for temperature sensors of the Platinum 100 (Pt100) type, enabling the differentiation of these sensors based on their response characteristics. On the contrary, the sensors of the Pt1000 type did not display such distinct behaviour, as some of these sensors result in exactly the same binary response. In general, our work offers a systematic approach towards the creation of PUFs based on temperature-dependent resistors, paving the way for their use in enhancing the security of the devices in which these sensors are incorporated.