Efficiency Comparison of Different DC-DC Converter Architectures for a Power Supply of a LiDAR System Ruben E. Figueiredo 1 , Vitor Monteiro 1 , Jose A. Afonso 2 , J. G. Pinto 1 , Jose A. Salgado 1 , Luiz A. Lisboa Cardoso 1 , Miguel Nogueira 3 , Aderito Abreu 3 , Joao L. Afonso 1 1 ALGORITMI Research Centre, University of Minho, Guimarães, Portugal 2 CMEMS-UMinho Center, University of Minho, Guimarães, Portugal 3 Bosch Car Multimedia Portugal, S.A. Rua do Barrio de Cima, nº1, 4705-820 Braga, Portugal ruben.figueiredo@algoritmi.uminho.pt Abstract. LiDAR (Light Detection And Ranging) is a technology used to meas- ure distances to objects. Internally, a LiDAR system is constituted by several components, including a power supply, which is responsible to provide the dis- tinct voltage levels necessary for all the components. In this context, this paper presents an efficiency comparison of three different DC-DC converter architec- tures for a LiDAR system, each one composed of three DC-DC converters: in parallel; in cascade; and hybrid (mix of parallel and cascade). The topology of the adopted integrated DC-DC converters is the synchronous buck Switched- Mode Power Supply (SMPS), which is a modified version of the basic buck SMPS topology. Three distinct SMPSs were considered: LM5146-Q1, LM5116, and TPS548A20RVER. These SMPSs were selected according to the require- ments of voltage levels, namely, 12 V, 5 V, and 3.3 V. Along the paper, the prin- ciple of operation of the SMPSs is presented, as well as the evaluation results obtained for different operating powers, allowing to establish a comprehensive efficiency comparison. Keywords: LiDAR, DC-DC Converters, Efficiency Comparison, Synchronous Buck, Switched Mode Power Supply. 1 Introduction Autonomous vehicles are identified as the main booster in terms of future intelligent transport in smart and sustainable cities [1]. Within this context, LiDAR (Light Detec- tion and Ranging) is one of the key sensing technologies required to enable partial or fully autonomous driving [2]. Specifically, LiDAR is an active remote sensing method that works on the same principle of sonar, but using laser pulses to build a 3D model of the environment around. Internally, a LiDAR system is constituted by several parts such as a laser source capable of transmitting pulsed or continuous light, a low noise high- speed receiver capable of detecting and processing the reflected light beam and a low power controller unit, where the power supply is a common system to all the parts,