A 77 GHz High Power and Gain Transformer-Coupled Amplifier in CMOS FD-SOI 28 NM

In this paper, a millimeter-wave high power and gain transformer-coupled amplifier is proposed. Designed in CMOS FD-SOI 28 nm technology and operating at 77 GHz, the 3-stage cascode power amplifier presents a 2-way differential structure based on integrated mm-wave transformers to provide high output power in a compact implementation. The substrate biasing feature of the technology was used to maximize the output power. Then, the transformers were implemented in the uppermost layers of the back end of line with a floating shield in the lower layers, to improve isolation and assure minimum insertion loss bellow -10 dB and a common-mode rejection ratio up to 26 dB. Post-layout simulations exhibited an output statured power of 18.36 dBm, a 1-dB output compression point of 16.5 dBm, a power gain of 44 dB and a peak power added efficiency of 9 %, at 77 GHz, while the PA occupies a compact active area of (960 * 720) μm
²
.