Choi Shinhae, Chon Yeojin, Park Sung Min
Division of Electronic & Semiconductor Engineering, Ewha Womans University, Seoul 03760, Republic of Korea.
Graduate Program in Smart Factory, Ewha Womans University, Seoul 03760, Republic of Korea.
Micromachines (Basel). 2024 Aug 23;15(9):1066. doi: 10.3390/mi15091066.
This paper presents a novel power-efficient topology for receivers in short-range LiDAR sensors. Conventionally, LiDAR sensors exploit complex time-to-digital converters (TDCs) for time-of-flight (ToF) distance measurements, thereby frequently leading to intricate circuit designs and persistent walk error issues. However, this work features a fully differential trans-impedance amplifier with on-chip avalanche photodiodes as optical detectors so that the need of the following post-amplifiers and output buffers can be eliminated, thus considerably reducing power consumption. Also, the combination of amplitude-to-voltage (A2V) and time-to-voltage (T2V) converters are exploited to replace the complicated TDC circuit. The A2V converter efficiently processes weak input photocurrents ranging from 1 to 50 μA which corresponds to a maximum distance of 22.8 m, while the T2V converter handles relatively larger photocurrents from 40 μA to 5.8 mA for distances as short as 30 cm. The post-layout simulations confirm that the proposed LiDAR receiver can detect optical pulses over the range of 0.3 to 22.8 m with a low power dissipation of 10 mW from a single 1.8 V supply. This topology offers significant improvements in simplifying the receiver design and reducing the power consumption, providing a more efficient and accurate solution that is highly suitable for short-range LiDAR sensor applications.
本文提出了一种用于短程激光雷达传感器接收器的新型高效节能拓扑结构。传统上,激光雷达传感器利用复杂的时间数字转换器(TDC)进行飞行时间(ToF)距离测量,从而常常导致复杂的电路设计和持续的走步误差问题。然而,这项工作采用了一种带有片上雪崩光电二极管作为光探测器的全差分跨阻放大器,这样就可以消除对后续后置放大器和输出缓冲器的需求,从而大幅降低功耗。此外,利用幅度到电压(A2V)和时间到电压(T2V)转换器的组合来取代复杂的TDC电路。A2V转换器有效地处理范围为1至50 μA的微弱输入光电流,这对应于最大22.8 m的距离,而T2V转换器处理40 μA至5.8 mA的相对较大光电流,用于最短30 cm的距离。布局后仿真证实,所提出的激光雷达接收器能够在0.3至22.8 m的范围内检测光脉冲,从单一1.8 V电源获取的功耗仅为10 mW。这种拓扑结构在简化接收器设计和降低功耗方面有显著改进,提供了一种更高效、准确的解决方案,非常适合短程激光雷达传感器应用。