A 2.4-GHz/3.5-GHz/5-GHz multi-band LNA with complementary switched capacitor multi-tap inductor in 0.18μm CMOS

This paper proposes a multi-band low noise amplifier design for WMAN and WLAN applications. The target frequency bands include licensed bands of 2.3 GHz, 2.5 ~ 2.7 GHz and 3.5 ~3.7 GHz, and un-licensed bands of ISM 2.4 GHz and U-NII 5 GHz. The LNA adopts a band selection technique that uses a multi-tap inductor with complementary switch capacitor array. The measured NFs and IIP3s of the proposed LNA are 6.5 dB and -3 dBm at 2.4 GHz, 7.6 dB and -5 dBm at 3.5 GHz, and 8.5 dB and +1 dBm at 5.2 GHz, respectively. The insertion gain S21's are 15 dB at 2.4 GHz, 17 dB at 3.5 GHz, and 15.4 dB at 5.4 GHz. Using a 0.18μm CMOS process, the multi-band LNA dissipates 14.6 mW at 2.4 GHz, and 27.7 mW at 3.5 and 5 GHz without output buffer from a 1.8-V supply voltage