A 36× 7 scanning LiDAR sensor with full coincidence detection for background light suppression

Abstract

This paper presents a scanning light detection and ranging (LiDAR) with a 36 × 7 array, integrated with coarse and fine quantization time to digital converters (TDCs). A novel coincidence detection circuit is proposed to mitigate the issues of miscounts and missed counts commonly encountered in conventional methods. Furthermore, the system employs a hybrid architecture that combines successive approximation with pipelining, enabling parallel binary quantization of each stage. The chip is designed using a 110 nm CMOS process with a total area of $1.15{\mathrm{mm}}^2$. The coarse quantization TDC adopts an analog counter design, achieving a compact macro-pixel size of $55\times 55{\mu m}^2$. The simulation results demonstrate that the proposed coincidence detection circuit exhibits a higher success rate under varying background light intensities and distances, and the system achieves a depth precision of 0.18% over a measurement range of 48 meters with a frame rate of 50 fps.