E-band transformer-based Doherty power amplifier in 40 nm CMOS

This paper presents an 80 GHz Doherty power amplifier in 40 nm CMOS technology. The amplifier combines 4 push-pull amplifiers by using 2×2 parallel-series combiner. In addition, it employs additional LC impedance matching to enhance the back-off efficiency. The transformer-based Doherty amplifier demonstrates both high linearity and high back-off efficiency. Thus, it is tailored for high PAPR mm-wave applications such as E-band communication. The two stage Doherty power amplifier achieves 16.2 dBm output power at 0.9 V supply with a PAE of 12%. Thanks to the linearization feature of the Doherty topology the 1 dB compression point of the amplifier is as high as 15.2 dBm while the PAE at P
_1dB
is 11.1%.