Micropower CMOS lock-in amplifier for portable applications

摘要

A new fully integrated micropower CMOS analogue lock-in amplifier (LIA) is presented. To achieve a compact architecture able to operate under low voltage with low-power consumption, it is based on a current-mode amplifier with embedded rectification within the transconductance stage. Post-layout results for a 0.18 µm CMOS implementation show a dynamic reserve of 51.2 dB, a power consumption of 482 µW and an integration area of 0.03 mm. The frequency operation ranges from 450 Hz to 1.1 MHz, whereas the gain is programmable from 39 to 59 dB, providing the LIA with flexibility to match a wide range of applications.