Straintronics-Based True Random Number Generator for High-Speed and Energy-Limited Applications

Random number generators are well known for their ubiquitous use in cryptography, statistical sampling, and computer simulations. In order to establish secure data transfers in cryptographic applications, these number generators need to reliably produce unpredictable numbers at a high rate. In this paper, by exploiting the metastability of the stressed straintronics (STR) device, we theoretically propose a proof-of-concept nanomagnetic-based scheme to generate random numbers at very high rates with low-energy overhead. The dynamic modeling of the device, including the Langevin thermal noise field, is discussed, and the effect of process variation on the energy barrier and reliability is analyzed. The device is interfaced with CMOS circuitry and simulated in the 65 nm technology. At 1 V supply level, the system can generate random numbers as fast as 510 MHz. The entire circuit, including the CMOS peripherals, consumes 12.5 uW at 100 MHz random number generation rate while dissipating merely 0.125 pJ/bit. By reducing the supply level to 0.5 V, the energy per bit can be reduced further to 19 fJ. Since the STR device can be placed on the top of the CMOS circuitry, the total area of the design is estimated to be 0.001 mm
²
.