A Ku-Band 3.3-V LNA With Multicoupled Q-Enhancement Transformer and Current-Reuse Techniques in 65-nm CMOS

This letter presents a Ku-band 3.3-V low-noise amplifier (LNA) with a multicoupled transformer using current-reuse techniques. The multicoupled transformer combines a shunt resonator and a series resonator forming multiple resonant frequencies. Furthermore, the topology enhances the equivalent $Q$ factor of the inductors for input matching and reduces the noise factors. Wideband input matching and noise matching are realized simultaneously. Fabricated in a 65-nm CMOS process, the LNA achieves a 1.58–2.63-dB NF and a 29.6-dB power gain from 9.5 to 13.5 GHz with a 1.5-dB ripple. The LNA consumes 20 mW from a 3.3-V supply and occupies an area of 0.39 mm2.