60 GHz 90nm CMOS wideband neutralized PA with 23dB gain and 20% PAE

This paper presents a 60GHz PA based on differential cross coupled (CC) transformer design. The 3-stage PA, fabricated in 90nm CMOS, achieves a 23dB gain with integrated baluns, maximum power added efficiency (PAE) of 19.5%, Psat of 9.5dBm with a 12GHz BW and 0.05mm² chip size. The paper shows the advantages of transformers and MOScap neutralization feedback for creating a state-of-the-art wideband efficient PA. An analysis of PA linearity is presented to reach record measured efficiency value of 7% at 4dB power backoff from P1dB.