Capacitor Cross-Coupled Fully-differential CMOS Folded Cascode LNAs with Ultra Low Power Consumption

This paper proposes a fully-differential folded cascode low noise amplifier (LNA) for 5.5 GHz receiver in 180 nm CMOS technology. By improving folded cascode with an additional inductance connected at the gate of CG stage to cancel parasitic capacitance and then employing capacitor cross-coupled technique as a negative feedback in the proposed LNA, the performance of the LNA can be improved significantly in terms of gain (S21) and noise figure (NF) compared with the conventional fold cascode LNA. Furthermore, the DC power consumption of the LNA is further reduced with forward body bias topology. The measurements show the proposed LNA achieves 16.5 dB power gain, a NF of 1.53 dB, good input/output matching with the S11 and S22 are less than (-) 15 dB. And the operating voltage is only 0.5 V with ultra-low power consumption of 0.89 mW.