A wideband transconductance enhancement CMOS LNA with multiple feedback technique

This work proposes a wideband transconductance enhancement CMOS LNA with multiple feedback technique. Two positive-feedback loops are used to alleviate the restricted gm value for input matching of the CG LNA. By using a triple-well process, the bulk cross-coupling connection between the common-gate amplifiers enhances the transconductance (gm) of the input stage, thus saving power consumption and reducing NF. A negative-feedback loop is also used to boost gm, lowering the input impedance and raising the voltage gain. An amplifier prototype was realized in 90-nm CMOS technology, operating from 10 to 1010 MHz, and dissipating 5.68 mW from 2-V supply while occupying a 0.048-mm2 core area. The LNA delivers a maximum power gain of 11.5 dB, a minimum NF of 2.14 dB, and a third-order intermodulation intercept point of -0.85 dBm.