A 32.9% PAE, 15.3 dBm, 21.6–41.6 GHz power amplifier in 65nm CMOS using coupled resonators

This paper presents a wideband millimeter-wave (mm-wave) power amplifier in 65nm CMOS. Coupled resonator based wideband matching technique is used in all the matching network. In the output matching network, the coupled resonator can achieve impedance transformation over a wide frequency range. In the input/inter-stage matching network, the uncoupled resonant frequencies of LC network at two sides of the coupled resonator are shifting towards opposite direction to extend the bandwidth and reduce ripple. The measured PA chip achieves 32.9% peak PAE, 15.3 dBm saturated output power. The fractional bandwidth is 63.3% from 21.6 to 41.6 GHz, which is the widest among reported bulk CMOS mm-wave PAs according to the authors' knowledge.