An Energy‐Efficient Capacitor Charger Converter for Low‐Power, Low‐Voltage Pulsed‐Power Supply System

ABSTRACT The pulsed power supply system is an effective approach for loads that require higher power than the supply power. This article proposes an efficient capacitor charger converter that can deliver high instantaneous power from a low‐power battery using an external capacitor. By switching at the boundary of continuous current mode (CCM) and discontinuous current mode (DCM), the charger converter charges the capacitor step by step. The majority of losses are related to conduction and switching losses during the charging process. Conduction loss is due to resistances in the inductor's current path. Switching loss is caused by the switching frequency of the output MOSFETs of the capacitor charger converter. The proposed structure significantly reduces the total conduction and switching losses by controlling the inductor current ripple and the capability of operating at low frequencies. By reducing losses during charging, the charging efficiency has increased, leading to improved efficiency of the entire proposed circuit. By resuming the charging process after delivering a high instantaneous power, the circuit reduces the load's sleep period and prevents the loss of capacitor's residual energy. The proposed structure was evaluated and simulated in a 0.18‐μm CMOS technology. The evaluation results indicate that the proposed pulsed power supply circuit performs better in various load consumption energy levels compared to previous structures. The circuit's efficiency for the energy consumed by the load in the 7.1‐ to 47.7‐μJ range reaches more than 94.6%.