A Double Pulse Overlapping Laser Diode Driver With Minimum 100-ps Pulse for LiDAR System

Light detection and ranging (LiDAR) technology is widely spreading to many applications. Among the various ranging methods, direct time of flight (dToF) stands out as particularly promising for real-time and long-range applications. However, the detection resolution and range of dToF LiDAR systems depend on the minimum width and maximum power of the emitted laser pulse. This work introduces a new laser diode driver (LDD) structure for high-resolution and long-range LiDAR transmitter (TX) system. It features a double pulse overlapping (DPO) scheme to generate ultra-short laser pulses spanning from 100 ps to 2 ns, achieving output pulsewidths significantly shorter than the control signal. Furthermore, two package configurations are implemented and an interleaved bonding method is analyzed and utilized to reduce the parasitic inductance and hence to improve the peak optical power. The parasitic effect analysis and system implementation circuit techniques are also presented. Fabricated in a 180-nm high-voltage BCD process, the two implemented TX systems achieve a minimum pulsewidth of 100 ps or a maximum output current of 15 A within 1-ns pulsewidth.