Transformer-Coupled D-Band PA with 11.8 dBm $\mathrm{P}_{\mathrm{sat}}$ and 6.3 % PAE in $0.13 \mu \mathrm{m}$ SiGe BiCMOS

In this paper we present a fully differential power amplifier (PA) in a 0.13 μm SiGe BiCMOS technology operating in D-Band. The PA has a maximum PAE of 6.3 %, a saturated output power of 11.8 dBm at a frequency of 114 GHz and is designed to an optimum load impedance different from 50 Ω offered by a chip to PCB transition. In the previously designed SiGe BiCMOS PAs for D-Band applications, interstage matching networks consist of transmission lines, whereas in this work a transformer is used because a transformer offers the advantage of being an efficient and compact higher-order filter. Therefore, the amplifier only occupies an active chip area of 0.19 mm
²
including baluns. In CMOS transformer-based coupling between the stages is quite common, whereas in SiGe this has not been demonstrated so far. Accordingly, to the authors best knowledge, this is the first D-Band SiGe PA using transformer-coupling.