A Unified Oscillator-Based TRNG and PUF with a Gate-Tunneling Entropy Source

In the world of IoT and embedded systems, security depends on reliable cryptographic circuits like Physical Unclonable Functions (PUFs) and True Random Number Generators (TRNGs) to verify devices and keep data secure. While these components are usually implemented separately, recent approaches suggest combining them can save space and increase efficiency. This paper introduces a unified design for both a TRNG and a PUF, using the same entropy source: the gate-tunneling currents found in CMOS transistors. By drawing on manufacturing imperfections, this approach creates both unique device identifiers and high-quality random bitstreams for secure operations. Through measurements and validation using the NIST SP 800-22 tests, we show that the design meets stringent randomness requirements. This integrated solution could provide a practical, efficient answer for security in resource-limited systems.