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arXiv · 2609.22665

Real-time Tunable Probability Distributions From Perimeter-Gated SPAD TRNGs

Yanbing Icey Chen·Md Sakibur Sajal·Marc Dandin
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Abstract

True random number generators (TRNGs) based on the dark noise of perimeter-gated single-photon avalanche diodes (pg-SPADs) naturally produce outputs that follow a tunable Bernoulli distribution. For applications requiring non-uniform random numbers, multiple such units can be coupled, or the inherent Poisson statistics of the accumulated dark events from a single pg-SPAD can be exploited. In this work, we present the principles for extending pg-SPAD-based TRNGs from the uniform to the non-uniform regime and investigate the impact of the perimeter-gate voltage on the underlying probability distributions. The proposed concepts were experimentally validated using a prototype 64 x 64 pg-SPAD chip, fabricated in a standard 0.35 $μ$m CMOS process. Collectively, we showed that common non-uniform distributions such as Poisson, exponential, and approximated Gaussian can be achieved and tuned in real-time using pg-SPAD TRNGs.

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Yanbing Icey Chen, Md Sakibur Sajal, Marc Dandin. 2026-09-19. Real-time Tunable Probability Distributions From Perimeter-Gated SPAD TRNGs. https://arxiv.org/abs/2609.22665

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