JSSC 2021第12期RF & Wireless40-nm

Quadrature Switched/Floated Capacitor Power Ampliﬁer With Reconﬁgurable Self-Coupling Canceling Transform er for Deep Back-Off Efﬁciency Enhancement Bingzheng Y ang

提出一种具有深度回退效率增强的正交开关/浮动电容功率放大器（SFCPA），通过可重构自耦合消除变压器（RSCCT）实现阻抗提升。

30.3-dBm饱和输出功率，36.6%/32.9%/29.1%/23.7%/18.6%/13.2%系统效率（SE），-31.9 dB EVM（256-QAM），-35.9 dB EVM（1024-QAM）

功率放大器深度回退效率正交开关浮动电容可重构自耦合

▸正交开关/浮动电容功率放大器（SFCPA）

▸可重构自耦合消除变压器（RSCCT）

▸IQ单元共享的瓦特级正交数字功率放大器（DPA）

Abstract

This article presents a quadrature switched/ﬂoated capacitor power ampliﬁer (SFCPA) with deep back-off efﬁ- ciency enhancement. The SFCPA is introduced to decrease the dynamic power consumption at power back-off (PBO), which could improve the system efﬁciency (SE). The recon- ﬁgurable 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 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 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 avg with an EVM of −35.9 dB and an average DE of 22.6%.