A reconfigurable dual‐band low noise amplifier for 5G in 65‐nm CMOS

Abstract

AbstractIn this paper, a reconfigurable low noise amplifier (LNA) is proposed for 5G dual‐bands in a 65‐nm CMOS process. The reconfigurable function of LNA is realized by designing reconfigurable matching networks composed of transformers and MOS transistor switches. The pole characteristics of the resonant network composed of the reconfigurable network and the equivalent circuit of the amplifying device are deduced and analyzed in detail. By establishing the relationship between two reconfigurable frequencies and the ratio of transformer coil inductance under two switching states, the position of the switch and the specific parameters of the reconfigurable matching network are determined. Measurement results show small‐signal gain of 25.5 to 33.9 dB and noise figure of 3.3 to 4.3 dB at 24 to 29.5 GHz bands, and small‐signal gain of 23.5 to 27.8 dB and noise figure of 4.3 to 4.5 dB at 37 to 40 GHz bands, respectively. The chip area occupied 0.34 mm2 including pads.