A low-power microphone preamplifier with EMI canceling

摘要

A low-power transadmittance amplifier is presented, that suppresses EMI by suppression of the detection mechanism as well as a compensation technique. The detection is suppressed by cancellation of the even harmonics. Compensation is achieved with the help of a dummy amplifier that reproduces the disturbance. The presented measurement results show that especially the compensation suppresses the EMI quite well.