Abstract: A novel and useful fully integrated switched-mode wideband 60 GHz power amplifier architecture. Using an appropriate second-harmonic termination of its output matching network, the required systematic peak current of the final stage is reduced such that the PA functions as a class-E/F2 switched-mode PA at saturation. In addition, low/moderate magnetic coupling factor transformers in the intermediate stages enable the PA to reach a high power added efficiency (PAE) and bandwidth product. Transformers of low/moderate coupling are also utilized in the preliminary stages of the PA to improve the overall bandwidth. In addition, the PA exploits the different behavior of the output impedance matching network for differential mode (DM) and common mode (CM) excitations. The PA is also stabilized against the combination of DM and CM oscillation modes. The PA also provides a technique to stabilize transformer-based mm-wave amplifiers against various modes of undesired oscillations.