High-Entropy Metastable Jitter-Based True Random Number Generator (TRNG)

True Random Number Generator (TRNG) is a pivotal component of hardware-security modules in IoT devices. In this paper, we propose a miniaturized Dual Input Metastable Jitter-based (DIMJ) TRNG. The core idea behind this design lies in leveraging metastability and inconsistent oscillations through self-coupling and a cross-coupling mechanism, effectively reducing circuitry while enhancing output diversity. The randomness of the proposed TRNG has been rigorously validated using a variety of statistical tests, including NIST SP800-90B, NIST SP800-22, AIS-31, as well as Autocorrelation and Deviation evaluation suites. Moreover, we achieved a near-perfect entropy of 0.999999 in the produced bit streams, yielding high security. In addition, the design possesses lightweight gate equivalent size and minimal resource utilization in Field-Programmable Gate Array (FPGA), maintaining optimal power consumption and throughput. However, the proposed circuitry is adaptable to be employed in bigger devices by incorporating multiple DIMJ modules in the design. Finally, the superior performance in randomness with compact architecture and optimal resource usage demonstrates its potential for hardware security modules.