A novel ultra wideband transformer-feedback LNA

Abstract

A 3-10 GHz wide-band low noise amplifier with novel input matching mechanism is presented in this letter. The proposed circuit uses reactive-feedback and transistor's intrinsic gate-drain capacitor as input matching network to achieve a simulated -10dB input reflection coefficient from 3.1 GHz to 10.6 GHz. The fabricated wideband LNA achieves a simulated power gain (S21) of about 10 dB from 3.1 G to 10.6 GHz, and noise figure of 2.72-3.26 dB from 3.1 G to 10.6 GHz. The input 1 dB compression point and input IP3 (IIP3) at 3.1 GHz are about -18.5 and -12 dBm, respectively. The DC supply voltage and power consumption is 1.5V(-) and 15 mA, respectively.