Compact high-power 60 GHz power amplifier in 65 nm CMOS

This paper presents a compact 60 GHz power amplifier utilizing a novel 4-way multi-conductor power combiner and splitter. The proposed topology provides the capability of combining the output power of four individual power amplifier cores in a compact die area of 0.025 mm² with the advantage of lower insertion loss and higher efficiency compared to the conventional distributed active transformer topology. Each power amplifier core consists of a three-stage common-source amplifier with transformer-coupled impedance matching networks. Fabricated in 65 nm CMOS process, the measured gain of the 0.19 mm² power amplifier is 18.8 dB at 60 GHz with 3dB band width of 4 GHz while consuming 424 mW from a 1.4V supply. A maximum saturated output power of 18.3dBm is measured with the 15.9% peak power added efficiency at 60 GHz.