Fast-gating of single-photon avalanche diodes with 200ps transitions and 30ps timing jitter

We present circuits and methods for fast-gating a silicon single-photon avalanche diode (SPAD) in order to attain wide dynamic range in the measurement of very faint and very fast optical signals. A mixed-signal amplifier comprising ECL logic and microwave components allows to achieve turn-ON and turn-OFF transition times below 200ps and gating windows from 10ns down to just few hundreds of picoseconds. A differential front-end electronics reads out the avalanche current pulse while rejecting spurious spikes due to the gate pulse, thus achieving a photon detection timing jitter below 30ps. This paper describes the conceived circuit solutions, the overall instrument development and the results of its characterization and validation.