CMOS Low Noise Amplifier with Capacitive Feedback Matching

A capacitive shunt feedback LNA input matching network is demonstrated which offers matching, good noise performance, low component count and low area consumption. A prototype 9 GHz LNA vehicle amplifier is designed and fabricated in a 130 nm RF-CMOS process. The measured amplifier has 20.5 dB of gain at 8.8 GHz with input and output match of -15 dB and -8 dB respectively. It has 1.4 GHz of 3 dB-bandwidth around 9 GHz with the noise figure of 1.7 dB at the center frequency and below 2 dB across the band. Large signal measurements reveal that the amplifier can deliver -2 dBm of power to the 50Omega output load at its 1 dB compression point. It draws 23 mA of current from a 1.2 V supply. The chip occupies an area of 0.64 mm².