A SPAD-based linear sensor with in-pixel temporal pattern detection for interference and background rejection with smart readout scheme

In this work, a 1x64 pixel SPAD-based linear sensor for direct time-of-flight (d-ToF) applications with real-time inpixel interference and background rejection is presented. Each pixel is composed by 4 SPADs with passive quenching, a digital logic circuit to exploit photon temporal coincidence with a threshold of up to 3 photons for background rejection, a finite state machine for the detection of temporal laser patterns for the rejection of interfering signals generated by other similar devices and a 16-b time-to-digital converter with 150 ps timing resolution that can be repurposed for intensity measurements. The sensor implements a smart readout scheme capable to output only pixels with meaningful data, i.e., detection events that have been validated by the photon temporal coincidence circuit and/or the laser pattern detection circuit