Inductorless Multi-Mode RF-CMOS Low Noise Amplifier Dedicated to Ultra Low Power Applications

This work presents and analyses the design of a multi-mode Low Noise Amplifier (LNA) dedicated to 2.4 GHz Wireless Sensor Network (WSN) applications. The proposed inductorless LNA, implemented in a 28 nm FDSOI CMOS technology, is based on a common-gate configuration imbedded with a common-source stage to boost the overall transconductance of the circuit. The LNA is specifically designed, and optimized, to address three modes of operation. The reconfiguration is performed through current tuning, combined with switching the back gate of the amplification transistors. The proposed implementation allows the figure of merit (FOM) to be maintained constant in the different modes of operation. In the low power mode, the LNA only consumes 350 uW. It achieves a voltage gain (G
_v
) of 16.8 dB and a noise figure (NF) of 6.6 dB. In the medium performance mode, the gain and the NF are respectively improved to 19.4 dB and 5.4 dB, the power consumption is 0.9 mW. In the high-performance mode, the gain is maximum, 22.9 dB, and the noise figure is minimum, 3.6 dB, for a power consumption of 2 mW. The linearity represented by the input referred third-order intercept point (IIP3) is constant, close to -16 dBm. The reported LNA occupies only 0.0015 mm
²
.