Low-loss 24-GHz passive baluns for on-chip integration

Two 24-GHz band passive baluns, a broadband planar transformer balun and a low loss lumped-element balun, are designed and characterized in 0.13 μm CMOS technology. The detailed design process is presented, including the topology selection, the inductor and transformer optimization, and the layout considerations. An impedance tuning method is implemented to efficiently and reliably integrate the balun with other circuits. The measurement results compare the state-of-the-art realizations.