An ultra-low voltage chaos-based true random number generator for IoT applications

Abstract

Low-power consumption and low-voltage operation are critical enabling features for Internet of Things (IoT) devices that are powered from energy harvesting. This paper presents a chaos-based true random number generator (TRNG) that can operate at an ultra-low voltage (ULV) and be integrated into energy-constrained IoT devices for secure communications. Folded Bernoulli maps are adopted for random number generation. Switched-capacitor chaotic circuits utilize bulk-driven amplifiers to mitigate gate leakage issue, two-stage comparators to increase voltage headroom, and low-complexity calibration schemes to ensure robustness. This system covers a wide range of process and temperature variations while consuming 142 nW from a 0.4 V supply at a bit rate of 10 kb/s. The generated bits pass National Institute of Standards and Technology (NIST) Pub-800.22 randomness tests successfully.