A 65nm CMOS front-end LNA for medical ultrasound imaging with feedback employing noise and distortion cancellation

A 70μW low power front-end Low Noise Amplifier (LNA) for ultrasound applications is proposed. The amplifier utilizes a balun based on a common-gate (CG) and a common-source (CS) combination. The CS-amplifier performs error correction, and thus cancels distortion and noise from the CG-amplifier. The amplifier is optimized towards low noise and low power consumption, and is a capacitive micro machined ultrasonic transducer (CMUT) tailored LNA. The LNA is design and simulated under 65nm CMOS technology, achieving a noise figure (NF) of only 2.98dB with a total power consumption of only 70μW. The amplifier is tuned towards an CMUT impedance of 10k/ -60° at a center of frequency 5MHz, with a input impedance of 3.8kΩ. Moreover, sporting a dynamic range (DR) of 50.53dB.