A 16 V-Output Switched-Capacitor Sigma Converter With 180 ns Transient Response and 94% Efficiency for LiDAR Receivers

Abstract

This article presents a step-up switched-capacitor (SC) sigma converter with fast transient, high efficiency, and high accuracy for light detection and ranging (LiDAR) receiver applications. The proposed sigma converter combines an unregulated SC converter in the high-voltage (HV) domain and a low-dropout (LDO) regulator in the low-voltage (LV) domain, achieving step-up voltage conversion through a series output connection. The unregulated SC converter operates in the HV domain, achieves high-efficiency power delivery, and boosts voltage in a very high density. At the same time, the LDO ensures fast transient response and accurate load regulation in the LV domain. The prototype achieves 5–16 V voltage boosting with a peak conversion efficiency of 94% at a maximum output power of 3.6 W and up to 152 mW/mm³ power density. The LDO regulator ensures accurate load regulation of 44 μV/mA (0.063% error with full load range) and fast load transient response of 180 ns during 0–200 mA load current transition.