A Scalable Multiphase Current-Mode Buck Controller With Sub-Milliohm DCR Current Sensing and Synchronized Overcurrent Protection
A Scalable Multiphase Current-Mode Buck Controller With Sub-Milliohm DCR Current Sensing and Synchronized Overcurrent Protection
复制标题
具有亚毫欧 DCR 电流感应和同步过流保护功能的可扩展多相电流模式降压控制器
DOI：
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发表时间：
2021
影响因子：
5.4
通讯作者：
E. Gu
中科院分区：
文献类型：
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作者：
Yingyi Yan;E. Gu
本文提出了一种可扩展的多相峰值电流模式降压控制器，具有亚毫欧直流电阻(DCR)电流检测和同步过流保护功能。低DCR电流检测能力是追求高效率和精确电流平衡的关键。为此，提出了一种亚毫欧DCR电流检测电路。各相的低频电流信号由分时放大器放大，输出分别与放大后的高频信号组合，重构成比例电流传感信号。给出了该传感方案的小信号分析和设计准则。所提出的电流检测方案提高了信噪比，改善了相间电流平衡，并显著减小了检测电路的硅面积。本文讨论了多芯片并行系统中打嗝模式过流保护的闭锁问题。设计了一种同步打嗝模式过流保护方案，在不增加系统额外通信总线的情况下解决了这一问题。该控制器采用0.6-$Mu Ext{m}$BiCMOS工艺制作，实验结果证明了电流检测电路和保护方案的有效性。
This article presents a scalable multiphase peak current-mode Buck controller with sub-milliohm direct current resistance (DCR) current sensing and synchronized overcurrent protection. Low DCR current sensing capability is critical in pursuing high efficiency and precise current balancing. For this purpose, a sub-milliohm DCR current sensing circuit is proposed. The low-frequency current signals from all the phases are amplified by a time-shared amplifier, and the outputs are combined with the exaggerated high-frequency signals, respectively, to rebuild the proportional current sensing signals. The small signal analysis and the design guidelines of the proposed sensing scheme are presented. The proposed current sensing scheme enhances the signal-to-noise ratio, improves the phase to phase current balancing, and dramatically reduces the silicon area of the sensing circuit. A latch-up problem of hiccup mode over current protection in the multi-chip parallel system is addressed in this article. A synchronized hiccup mode over current protection scheme is designed to solve the issue without adding extra communication bus to the system. The proposed controller is fabricated using a 0.6- $mu ext{m}$ BiCMOS process, and the experimental results prove the effectiveness of the current sensing circuit and protection scheme.