Wang, C.-W.C.-W.WangChen, Y.-C.Y.-C.ChenLin, W.-J.W.-J.LinTsai, J.-H.J.-H.TsaiTIAN-WEI HUANG2021-05-052021-05-0520200149645Xhttps://www.scopus.com/inward/record.url?eid=2-s2.0-85094216077&partnerID=40&md5=41557f907e134712e7f7528d119302c2https://scholars.lib.ntu.edu.tw/handle/123456789/559255This 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 (PSAT) 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 (Gp) of 20.4-dB at 23 GHz and a measured 3dB small-signal gain bandwidth (BW3dB) from 20.8 to 41.6 GHz covering the multiple 5G bands with only 39.6-mW quiescent power consumption. The measured Psat is 16.1-dBm at 30 GHz with over 50% Psat output power 1dB bandwidth (BW1\dB) from 23 to 38.5-GHz. Also, this PA reports a 35% peak power added efficiency (PAEMAX) at 25 GHz and a 13-dBm peak OP1\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. © 2020 IEEE.5G mobile communication; CMOS integrated circuits; Power amplifier; Transformer; Wideband5G mobile communication systems; Bandwidth; CMOS integrated circuits; Millimeter waves; Power amplifiers; Linear operations; Millimeter wave (MMW); Mobile communications; Output matching network; Resonant capacitors; Saturated output power (Psat); Small signal gain; Wideband power amplifier; Broadband amplifiersconference paper10.1109/IMS30576.2020.92239052-s2.0-85094216077