一种用于TOF激光雷达的多通道时数转换芯片设计

A Design of Multi-channel Time-to-digital Converter for TOF Lidar

摘要:

时间数字转换器(Time-to-Digital Converter,TDC)是一种将连续时间信号转换为数字信号输出的器件,是飞行时间(TOF)激光雷达中的关键部件。在利用计数器粗采样和多相位内插细采样的传统结构上,设计了一种基于相位内插的双级粗细结合型时间数字转换电路,并增加了双回波接收通路来接收多脉冲回波信号,在此基础上设计了一款17通道多路TDC系统芯片。芯片采用CMOS 0.11μm工艺设计,版图面积为0.6mm×3mm。后仿真结果显示,在1.2V电源下其功耗小于100mW,单输入精度平均值为51.7ps,动态范围为3.4μm,且线性度良好。该TDC芯片适用于飞行时间脉冲激光雷达的信号计时。

Abstract:

Time-to-digital converter (TDC) is a device for converting continuous time signal to digital signal, and it is the key component of TOF lidar. In this paper, designed is a two-stage coarse-fine combined time-to-digital converter circuit based on the traditional structure of counter coarse sampling and multi-phase interpolation fine sampling, and also a double echo receiving channel is added to receive multi-pulse echo signal. On this basis, a 17-channel multi-channel TDC system chip is designed. The system chip is designed with CMOS 0.11μm process, and the layout area is 0.6mm×3mm. The post simulation results show that the power consumption is less than 100mW, the average value of single input precision is 51.7ps, the dynamic range is 3.4μm, and chip presents good linearity under 1.2V power supply. Thus the TDC chip is suitable for signal timing of time-of-flight pulse lidar.