A 60-GHz CMOS power amplifier with Marchand balun-based parallel power combiner

A novel Marchand balun-based parallel power combiner suitable for a 60-GHz CMOS power amplifier is proposed. It improves the power efficiency by solving the issues of the phase difference of the signals to be combined and the low coupling factor of the on-chip balun in scaled CMOS technologies. The power amplifier using the proposed power combiner is fabricated in a 90 nm CMOS process with 1.2 V supply. Measured power gain, output referred 1-dB compression point, and saturated output power are 11.2 dB, +8.3 dBm, and +11.2 dBm, respectively, at 60-GHz.