Fully integrated power management circuits are promising candidates to provide small form factors and meet high power density demand of modern computing platforms. This article presents a new fully integrated dc–dc converter topology based on electromagnetically coupled class-D LC oscillators that enables up to 2.5 GHz switching frequency, allowing aggressive scaling of the on-chip passives. On-chip transformers and flying capacitors are designed to electromagnetically couple the two oscillators, and gigahertz-range switching frequency is achieved by the quasi-adiabatic switching of the parasitic capacitors. The proposed converter is implemented in a 0.18- μm\mu \text{m} CMOS process occupying 1.61 mm2 for 7.8 nH inductance (high efficiency version) and 0.37 mm2 for 3.1 nH (high power density version), achieving 1 W/mm2 peak power density. This work also proposes a duty-cycling scheme that improves the efficiency under light loads, which stays close to the peak from 4 μW4~\mu \text{W} up to 0.5 W, and in continuous operation mode the output voltage ripple is 12 mV without attaching any output capacitor thanks to the four-phase electromagnetic power delivery scheme.

中文翻译：

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使用电磁耦合 D 类 LC 振荡器的 1.25GHz 全集成直流转换器


全集成电源管理电路是提供小尺寸并满足现代计算平台高功率密度需求的有希望的候选者。本文介绍了一种基于电磁耦合 D 类 LC 振荡器的全新完全集成 DC-DC 转换器拓扑，可实现高达 2.5 GHz 的开关频率，从而实现片上无源器件的大幅扩展。片上变压器和飞跨电容器被设计用于电磁耦合两个振荡器，并且通过寄生电容器的准绝热开关实现千兆赫范围的开关频率。所提出的转换器采用 0.18- μm\mu \text{m} CMOS 工艺实现，占用 1.61 mm2，实现 7.8 nH 电感（高效版本），占用 0.37 mm2，实现 3.1 nH（高功率密度版本），实现 1 W/mm2 峰值功率密度。这项工作还提出了一种提高轻负载下效率的占空比方案，从 4 μW4~\mu \text{W} 到 0.5 W 都保持接近峰值，在连续工作模式下，输出电压纹波为 12由于采用四相电磁功率传输方案，无需连接任何输出电容器即可达到 mV。