High-Entropy STT-MTJ-Based TRNG

Hardware true random number generators (TRNGs) yield random numbers from physical processes. Traditionally, such devices are based on statistically random events such as thermal noise or other quantum phenomena. In this brief, we propose a novel TRNG design using a spin-transfer torque magnetic tunnel junction (MTJ) device. Our solution exploits the stochastic nature of the MTJ switching, and the behavior of an XOR gate dealing with probabilistic signals. We show that by using multiple MTJ devices, the proposed TRNG succeeds in filtering the negative effect of environmental changes as well as fabrication-induced variability and generates random sequences with high-entropy under any conditions.