A 50–82 GHz broadband cascode-based power amplifier in 40 nm CMOS

Abstract

In this paper, we present a broadband two-stage cascode-based power amplifier (PA) in 40 nm CMOS technology that covers the ISM band applications at 60 GHz, E-band applications channels (71–76 GHz, 77 GHz, 81–86 GHz), and Automotive radar application at 77 GHz. The bypass capacitor at the gate of the upper transistor of the cascode, which controls the swing, stability, and gain compression significantly, is studied and optimized carefully. Furthermore, a holistic design approach is provided to further optimize the input, output and interstage wideband matching networks to simultaneously improve the output power and gain performance over the whole operating frequency band. The measurement results show a power gain of 13 ± 1.5 dB, a maximum power added efficiency (PAE) and output gain compression point (POut1dB) of 15% and 11 dBm, respectively, while consuming 130 mW. Additionally, the PA achieves low measured group delay variations of 20 ± 10 ps and small measured AM-PM distortion < 3 degrees over the whole band.