An 18-dBm, 57 to 85-GHz, 4-Stack FET Power Amplifier in 45-nm SOI CMOS

A single stage, 4-stack FET SOI CMOS power amplifier (PA) demonstrates to the author’s knowledge the widest bandwidth covering 57 through 85 GHz for a CMOS PA while delivering a peak 18 dBm of output power. The 4-stack topology is also demonstrated for the first time in W-band to provide high output voltage swing while avoiding premature device aging and breakdown. The wideband performance results from a proposed series-shunt interstage matching network between the stacked FETs. The PA achieves a peak PAE of 20% and 12-dB gain with a 4.8-V power supply. The millimeter-wave PA is implemented in GlobalFoundries 45-nm SOI CMOS technology using a trap-rich substrate. A compact chip area of 525 µm × 300 µm is shown excluding pads.