Figure-of-merit optimization of a low noise amplifier in 180 nm CMOS

This paper presents the design of a low noise amplifier in 180 nm CMOS based on a figure-of-merit optimization technique. The proposed figure-of-merit for the given amplifier topology combines the trade-off between accuracy and current consumption, which is a typical trade-off for most low noise amplifiers. In addition, the chosen figure-of-merit is shown to have similar form as the figure-of-merit most commonly used to compare analog-to-digital converters today. The figure-of-merit optimization technique has been applied to a given low noise amplifier topology to achieve good design trade-offs and as a proof of concept. The low noise amplifier topology, intended to be used as a front-end amplifier for ultrasound imaging, has been simulated in 180 nm CMOS to confirm the optimal trade-off, and results indicate that the given design approach achieves relatively good performance. In addition to performing a single-ended to differential conversion, the designed amplifier achieves a noise figure of 1.89 dB at 7 MHz while draining 492 μA from the 1.8 V supply.