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arXiv · 2603.19304

A 320x240 SPAD dToF Flash LiDAR sensor combining TDC and multi-time-gating, achieving 108m range for LiDAR and AR/VR applications

Abstract

We propose a joint TDC and multi-time-gated imaging single-photon avalanche diode LiDAR sensor featuring a maximum detection range of 108m with a minimum depth resolution (least significant bit) of 2.93mm, fabricated in 110nm CMOS technology. The sensor is implemented 320x240 pixels with a pitch of 23{\mu}m, achieving a maximum fill factor of 10% and a total size of 8.2mmx6.3mm. The power consumption of the pixel array is 167.4mW. Under a repetition rate of 3.125MHz, a laser power of 11.3mW, and a wavelength of 780nm, the sensor is designed to operate at up to 100klx background illumination with a centimetric depth precision. It can be further improved to 130klx by reducing image resolution to 160x120 pixels. In addition, the sensor can reconfigure the idle TSPCs integrated in the cluster into counters for histogramming, thereby reducing the size of the data processing module.

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Chang Liu, Edoardo Charbon. 2026-03-13. A 320x240 SPAD dToF Flash LiDAR sensor combining TDC and multi-time-gating, achieving 108m range for LiDAR and AR/VR applications. https://arxiv.org/abs/2603.19304

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