A 6 to 18 GHz flat high gain power amplifier using mismatch-consistent MCR technique in 40-nm CMOS

Abstract

This paper presents a power amplifier (PA) based on the mismatch-consistent magnetically coupled resonator (MCR) technique, which employs adjustable dual-pole to achieve a wide operating frequency range. The in-band no gain ripple condition of the proposed mismatch-consistent MCR is systematically analyzed and derived. By applying this condition to the mismatch-consistent MCR technique, the in-band gain flatness in broadband is improved. An ultra-wide wiring method for the power-combining structure is proposed to further improve the in-band gain flatness by reducing parasitic effects. Meanwhile, an active broadband matching network without any on-chip inductor is used to obtain a -11 dB input return loss (S11) across the whole bandwidth. Implemented in 40-nm CMOS process, the proposed PA achieves a saturated output power of 19.2 dBm, an output 1 dB compression point of 17.8 dBm, a peak power added efficiency of 29.7 %, and only 0.5 dB in-band gain ripple at 8.2-16.2 GHz. The amplifier achieves a 3 dB bandwidth from 6 to 18 GHz while the fractional bandwidth reaches 100 %, realizing wideband and flat frequency response.