A 60-GHz 20.6-dBm Symmetric Radial-Combining Wideband Power Amplifier with 20.3% Peak PAE and 20-dB Gain in 90-nm CMOS

A 60-GHz 1.2-V wideband power amplifier (PA) with a compact 4-way radial power combiner implemented in 90nm CMOS process is presented in this paper. The transformer based radial power combiner with 1-dB insertion loss at 60 GHz and 0.043-mm(2) compact size is designed for high output power combining and wideband load-pull matching. This PA achieves saturated output power (P-SAT) of 20.6 dBm, maximum power added efficiency (PAE(max)) of 20.3%, and 20.1-dB small-signal gain (S-21) at 60 GHz. The PA maintains flat 20-dBm P-SAT with PAE(max) better than 17.3% within 50-64 GHz, and it has a 3-dB bandwidth (3-dB BW) of 24.5 GHz (41.8-66.3 GHz). The chip area without pads is 0.432 mm(2). To the author's best knowledge, this PA with flat 20-dBm P-SAT presents the widest large-signal bandwidth (50-64 GHz) compared to other 60-GHz CMOS PA.