An E-Band Power Amplifier With Broadband Parallel-Series Power Combiner in 40-nm CMOS

This paper describes a fully integrated E-band power amplifier (PA) in 40-nm CMOS. The design and layout of the unit PA stage is optimized to achieve high output power while maintaining high power gain. A broadband parallel-series power combiner is proposed to provide the PA stage optimum load impedance across the complete E-band. The complete PA achieves a measured saturated output power of 20.9 dBm with more than 15-GHz small-signal -3-dB bandwidth and 22% power-added efficiency (PAE) at 0.9-V supply. The in-band variation of -1-dB compressed power (P1 dB) is only ±0.25 dB. This is the first reported silicon-based PA that covers both 71-76- and 81-86-GHz bands with uniform gain, output power, and PAE.