This article presents a quadrature switched/floated capacitor power amplifier (SFCPA) with deep back-off efficiency enhancement. The SFCPA is introduced to decrease the dynamic power consumption at power back-off (PBO), which could improve the system efficiency (SE). The reconfigurable self-coupling canceling transformer (RSCCT) with enhanced tuning range of turn ratio is used to achieve impedance boosting for further improved efficiency at deep PBO. Based on the proposed SFCPA, a watt-level quadrature digital power amplifier (DPA) with IQ cell sharing, hybrid Doherty, and impedance boosting is proposed for deep PBO efficiency enhancement. Implemented in 40-nm CMOS, the proposed DPA with 1.2-/2.4-V supply achieves 30.3-dBm saturated output power ( $P_{\mathrm{ out}}$ ) with 36.6%/32.9%/29.1%/23.7%/18.6%/13.2% SE for 0-/3-/6-/9-/12-/15-dB PBOs at 2.4 GHz. For 60-MHz 256-QAM modulation signal, it delivers 23.32-dBm average output power ( $P_{\mathrm{ avg}}$ ) with an error vector magnitude (EVM) of −31.9 dB and an average drain efficiency (DE) of 30.7%. For 40-MHz 1024-QAM signal, it shows 20.44-dBm $P_{\mathrm{ avg}}$ with an EVM of −35.9 dB and an average DE of 22.6%.

中文翻译：

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具有可重配置自耦合消除变压器的正交开关/浮动电容器功率放大器，用于提高深度回退效率

本文介绍了一种具有深度回退效率增强的正交开关/浮动电容器功率放大器 (SFCPA)。引入 SFCPA 是为了降低功率回退 (PBO) 时的动态功耗，从而提高系统效率 (SE)。具有增强的匝数比调谐范围的可重构自耦合消除变压器 (RSCCT) 用于实现阻抗提升，以进一步提高深度 PBO 的效率。基于所提出的 SFCPA，提出了一种具有 IQ 单元共享、混合 Doherty 和阻抗提升的瓦级正交数字功率放大器 (DPA)，以实现深度 PBO 效率增强。在 40-nm CMOS 中实施，建议的具有 1.2-/2.4-V 电源的 DPA 实现了 30.3-dBm 的饱和输出功率（ $P_{\mathrm{ out}}$ ) 36.6%/32.9%/29.1%/23.7%/18.6%/13.2% SE，对于 2.4 GHz 的 0-/3-/6-/9-/12-/15-dB PBO。对于 60-MHz 256-QAM 调制信号，它提供 23.32-dBm 的平均输出功率 ( $P_{\mathrm{ 平均}}$ ) 的误差矢量幅度 (EVM) 为 −31.9 dB，平均漏极效率 (DE) 为 30.7%。对于 40-MHz 1024-QAM 信号，它显示 20.44-dBm $P_{\mathrm{ 平均}}$ 具有 -35.9 dB 的 EVM 和 22.6% 的平均 DE。