Abstract: In order to measure the flight time of photons，and improve the distance of laser radar ranging and ensure the stability of minimum time resolution，A pixel-level high dynamic range 16-bit time-to-digital converter is designed． The resolution is less than 330 ps and the detectable distance is more than kilometers． This design uses Xfab 0． 18 μm CMOS process for tapeout verification．

Key words: single-photon detection, time-to-digital converter, time of flight