A multi-mode configurable physical unclonable function based on RRAM with adjustable programmable voltage

Resistive random access memory (RRAM) presents a promising solution for energy-efficient logic-in-memory (LiM) systems. This paper introduces a Multi-mode Configurable Physical Unclonable Function (MC-PUF) tailored for secure RRAM-based LiM applications, utilizing a conventional one-transistor-one-RRAM (1T1R) array. The MC-PUF operates in multiple modes by modifying the programming voltages of the RRAM, which captures the distinct variations of each RRAM under varying conditions. In weak write mode, the MC-PUF exploits the inherent variations of RRAM by setting the programming voltages to achieve a 50% switching probability, thereby randomly assigning ‘0’ or ‘1’ states. In parallel competition mode, it generates responses by selecting two parallel RRAMs, with one remaining in a high resistance state (HRS) and the other switching to a low resistance state (LRS). This configuration allows the MC-PUF to generate more challenge-response pairs (CRPs) compared to conventional designs, thus enhancing security through increased entropy. The design was validated through simulations using a compact Spice model and the UMC 55 nm CMOS library, as well as on an experimental hardware platform with commercial RRAM chips. Results from both simulations and hardware implementations indicate that the proposed MC-PUF exhibits high reliability, excellent uniqueness, and superior configurability.