关键词: 窄脉冲驱动, GaNFET, 激光雷达, 裸芯片封装, 分离式放电环路, 多层叉指结构

Abstract: The overall performance of LiDAR is closely related to the driving performance of the laser pulse, the existing narrow pulse laser drive design is mainly based on Si-based devices, which have a high degree of integration, but it is difficult to obtain a higher peak power output, and cannot well match the needs of further narrowing of the pulse width. Starting from the drive theory, the drive circuit model is established, the factors affecting the narrow pulse width of the laser, such as parasitic inductance, device packaging, and drive layout, are analyzed. Through the design of bare chip packaging, loop layout optimization, and multi-layer interdigital structure, matching the excellent switching characteristics of GaN FET, a narrow pulse laser output with a rise time of 2.01 ns, a pulse width of 4.05 ns, a repetition frequency of 500 kHz, and a peak power of 55 W is achieved, with good waveform quality, while the package integration can be improved by more than 50%, which can lay the foundation for the development of next-generation high-precision, long-range, array-integrated LiDAR system.

Key words: narrow pulse drive, GaN FET, LiDAR, bare chip packaging, split discharge loop, multi-layer interdigital structure