A 140-GHz 14-dBm Power Amplifier using Power Combiner based on Symmetric Balun in 65-nm Bulk CMOS

This paper proposes a 140-GHz power amplifier (PA) with 14-dBm saturated output power. Our PA uses a symmetric-balun-based power combiner in D-band, which relaxes the impedance matching with the former-stage amplifiers thanks to the balanced input impedance. The PA prototypes have been designed in 65-nm bulk CMOS process. The 2-parallel PA achieves 6.0 dBm OP1dB with measurement, and 11.4 dBm saturated output power is expected with simulation. The performance of the 4-parallel PA is verified with simulation that shows 9.4 dBm OP1dB and 14 dBm saturated output power.