A 20.8-41.6-GHz Transformer-Based Wideband Power Amplifier with 20.4-dB Peak Gain Using 0.9-V 28-nm CMOS Process

摘要

This paper presents a wideband transformer-based power amplifier applicable for the millimeter-wave (MMW) fifth generation (5G) mobile communication. The proposed power amplifier is manufactured in 28-nm HPC-plus CMOS process. The power stage and driver stage amplifiers are biased in deep class-AB to reduce the dc power dissipation in the linear power region and provide a linear operation close to the saturated output power ($P_{SAT}$) of the PA. In the output matching network, a transformer with two coupled resonant capacitors is designed for broadband power matching. The proposed PA achieves the peak small-signal power gain ($G_{p}$) of 20.4-dB at 23 GHz and a measured 3dB small-signal gain bandwidth ($BW_{3dB}$) from 20.8 to 41.6 GHz covering the multiple 5G bands with only 39.6-mW quiescent power consumption. The measured $P_{mathrm{sat}}$ is 16.1-dBm at 30 GHz with over 50% $P_{mathrm{sat}}$ output power 1dB bandwidth ($BW_{1mathrm{dB}}$) from 23 to 38.5-GHz. Also, this PA reports a 35% peak power added efficiency ($PAE_{mathrm{MAX}}$) at 25 GHz and a 13-dBm peak $OP_{1mathrm{dB}}$ at 41 GHz. In the 64-QAM OFDM modulated signal measurement, this power amplifier obtains an output power of 7.2/6.9-dBm and a modulated PAE of 8.5%/8.8% at 23 and 41-GHz respectively when keeping the EVM below -25 dBc.