中圖分類號：TN433 文獻標志碼：A DOI: 10.16157/j.issn.0258-7998.256696
中文引用格式： 康端剛，康婷，李輝，等. LDO啟動浪涌的反饋網(wǎng)絡優(yōu)化抑制方法研究[J]. 電子技術應用，2025，51(10)：42-46.
英文引用格式： Kang Duangang，Kang Ting，Li Hui，et al. Research on feedback network optimization-based suppression method for LDO startup inrush current[J]. Application of Electronic Technique，2025，51(10)：42-46.

Research on feedback network optimization-based suppression method for LDO startup inrush current

Abstract： As a core power management component in modern electronic systems, the startup inrush current of Low Dropout linear regulators (LDO) poses significant threats to system reliability. This paper focuses on the MSK5101 LDO, addressing the input inrush current spike phenomenon observed after implementing an RC delay circuit at the enable terminal. A suppression method based on dynamic optimization of feedback networks is proposed. Through establishing a small-signal model and conducting frequency-domain analysis, the influence patterns of feedback network parameters on system response speed and stability are revealed. The proposed approach achieves equivalent soft-start functionality by increasing feedback resistance and adjusting compensation capacitance. Experimental results demonstrate that the optimized configuration reduces inrush current peak from 2.7 A to 0.87 A (a reduction of 67.8%), while extending output voltage settling time from 2.9 ms to 12.3 ms, significantly enhancing the stability and reliability of aerospace power systems.

Key words : low dropout linear regulator （LDO）；startup inrush current；feedback network optimization；soft-start；power management