A spin orbit torque based true random number generator with real-time optimization

Abstract

True random number generators (TRNG) is desired by various applications such as data encryption and statistical sampling. Due to the stochastic switching behavior, spin transfer torque magnetic tunnel junction (STT-MTJ) is used for the design of TRNG. However, it requires a high-complexity circuit to precisely control the duration and amplitude of the applied current. In this work, we propose a spin orbit torque MTJ based TRNG (SOT-TRNG) with a correction circuit. The controlling of the current is simplified, and the optimization modules are easy to be implemented. The transient simulation and the National Institute of Standards and technology (NIST) tests results demonstrate that the proposed TRNG can generate true random numbers with high speed meanwhile tolerate process, voltage, and temperature (PVT) variations. Furthermore, the comparison results show that the SOT-TRNG has a wider operational margin of current and stronger robustness.