We present the design of a new fast-gated 16 x 16 silicon SPAD array developed in a 0.16 μm BCD technology with builtin 6 ps resolution TDCs (Time-to-Digital Converters), optimized for Non-Line-Of-Sight imaging. The high temporal resolution is achieved by sharing one high-performance TDC among 16 SPADs, without losing spatial resolution, thanks to an identification logic capable of detecting and rejecting collisions. In the SPAD frontend, a low-threshold comparator minimizes temporal jitter, while an active quenching circuit reduces afterpulsing. An event-driven readout scheme optimizes data transfers, however a standard frame-driven photon-counting only mode is also available. The goal is to enable quasi real-time NLOS scene reconstruction by parallelizing the acquisition across multiple spots. Thanks to its high temporal resolution, the detector can be exploited also in other scientific applications, such as clinical diagnostic (with Time-Domain Near Infrared Spectroscopy) and LiDAR (Light Detection and Ranging).
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