A Tunable Dynamic Range Digital Single Photon Avalanche Diode

We characterize a digital, tunable dynamic range, single photon avalanche diode (SPAD) pixel fabricated in a standard 0.5 μm, 2-poly, 3-metal CMOS process. The principal sensor used in the pixel is based on the perimeter gated SPAD. The perimeter gate enhances device performance through prevention of premature breakdown, with the added advantage of a tunable dynamic range. Experimental measurements of the signal-to-noise ratio over the visible spectral range show the perimeter gate improves the dynamic range at a small expense of the sensitivity.