A 30-40 GHz Continuous Class F−1 Power Amplifier with 35.8% Peak PAE in 65 nm CMOS Technology

This paper presents a continuous-mode inverse Class-F (i.e., Class-F-1) power amplifier design to achieve both high efficiency and wide bandwidth for 5G communications. The proposed fundamental and harmonic matching is achieved using an output transformer with an embedded capacitor for continuous inverse class-F operation. In this way, we can reduce the harmonic load complexity and insertion loss greatly. Therefore, the proposed inverse Class-F PA shows a saturated output power (Psat) of 17.9 dBm, output power bandwidth (30 to 40 GHz) with 33 % peak PAE, and output 1-dB compression point (OP1dB) of 15.0 dBm at 34 GHz. When tested with a single-carrier 64-QAM signal, this PA achieves bandwidth of 400 MHz, 14.1-dBm average output power, and 22.1% average PAE under root-mean-square (rms) error vector magnitude (EVM) −25.1 dB. Among all the published mm-Wave CMOS PAs, this PA shows outstanding large-signal performances and exceptional modulation capability.