20-GHz, 20-dBm pseudo-differential power amplifier in standard 90-nm CMOS

This paper presents a 20-GHz pseudo-differential power amplifier (PA) fabricated in a standard 90-nm Si-CMOS process. The pseudo-differential PA has a two-stage cascode configuration with differential input and output ports. Assuming the use of an off-chip transformer, the input impedance of each single PA is designed to be 6.25 Omega and the output impedance to be 25 Omega. The individual amplifier fabricated demonstrates a saturation power of 20 dBm with a linear gain of 18 dB at 20 GHz. The supply voltage is 2.4 V, and the chip size is 2.0 times 1.8 mm².