2012 Volume E95.C Issue 10 Pages 1666-1674
In this paper, a capacitive-cross-coupling common-gate (CCC-CG) LNA using capacitive feedback is proposed to improve the noise figure (NF). In the conventional CCC-CG LNA, the transconductance gm is determined by the input-matching condition while a lager gm is required to improve NF. gm of the proposed LNA can be increased and NF can be improved by using the added capacitive feedback. The analytical calculation shows that the proposed LNA can perform better than the conventional CCC-CG LNA. In the measurement results using a 0.18-µm CMOS technology, the gain is 10.4-13.4dB, NF is 2.7-2.9dB at 0.8-1.8GHz, and IIP3 is -7dBm at 0.8GHz. The power consumption is 6.5mW with a 1.8-V supply.