A 60-GHz Transformer-Based Power Amplifier Supporting 5G n263-band Applications.

In this paper, a 55-67 GHz transformer-based three-stage power amplifier (PA) fabricated in 65-nm CMOS technology is proposed. This power amplifier utilizes a differential common-source (CS) structure with neutralized capacitors to increase the gain and stability. By adding parallel capacitors or absorbing the device’s parasitic capacitor, leakage inductance can be resonated out and the operation frequency can be tuned to realize wideband performance. Based on the proposed structure, the PA features saturated output power $(\mathrm{P}_{sat})$ of 14.5 dBm with a peak power-added efficiency (PAE) of 21.7% under 1-V supply.