A frequency-selective nested dual-loop broadband low-noise amplifier in 90 nm CMOS

A broadband, frequency-selective low-noise amplifier (LNA) with at least 25 dB of rejection at frequencies below the L-band (includes GPS and GSM carriers) is fabricated in a 90 nm standard CMOS process. The proposed LNA can be used for broadband impulse-radio ultra-wideband (IR-UWB) and frequency modulated FM-UWB. The frequency-selective (3.5-10.5 GHz) LNA is power-to-current (P-I) configured and comprises nested reactive feedback loops: a positive current-to-current (I-I) feedback loop to boost the power gain and a negative I-I feedback loop for impedance and noise matching. The measured gain of the P-I LNA is 15±3 dB. It has a noise figure (NF) of 2.4±0.8 dB and a 1-dB gain compression point (P_-½dB) of -17.5±2.5 dBm. The die area of the LNA is 0.7×0.8 mm² and it consumes 9.6 mW from a 0.8 V power supply. The proposed P-I LNA is most suitable for a sub-1 V single-cell radios.