True Random Number Generation Using Dark Noise Modulation of a Single-Photon Avalanche Diode

This brief presents the application of perimeter-gated single-photon avalanche diodes (pg-SPADs) as true random number generators (TRNGs). Typical SPADs have been used as random number generators (RNGs) in photon-based or dark event-based configurations, and they utilize complex debiasing algorithms to increase their random bit efficiency (RBE). In contrast, we propose leveraging the dark count rate modulation property of pg-SPADs to enable true random number generation using simpler debiasing algorithms. Further, we demonstrate that perimeter gating may be used to maintain a constant dark count rate across a wide temperature range, conferring stability to the RNG in that range. A set of debiased random bits from a tested prototype chip was benchmarked against the National Institute of Standards and Technology (NIST) Statistical Test Suite (STS) with a success rate of 99.375%.