23-28 GHz Doherty Power Amplifier Using 28 nm CMOS for 5G Applications

This paper presents a Doherty power amplifier (DPA) designed to operate at the 23 – 28 GHz frequency band for 5G applications. The load network was designed by converting a transmission line-based DPA network to an equivalent transformer-based matching network. Broadband characteristics of the load network was achieved through balancing the impedance transformation ratio at the matching networks of the carrier and peaking amplifiers. The DPA was fully integrated with the 28 nm bulk CMOS process. The designed DPA exhibited gain of 14.0 – 18.5 dB, saturated output power of 11.9 – 12.3 dBm, peak power-added efficiency (PAE) of 19.4 – 26.0%, and PAE of 12.8 – 14.3% at 6 dB output power backoff (OBO) when measured with a continuous wave (CW) signal.