Operation Amplifiers in EMI Filter Insertion Loss Measurement Setup

Abstract

The paper deals with the measuring of the EMI filters insertion loss. Two variations of differential mode measurement setups are compared. Impedance transformers are used in the first setup. Active devices (operational amplifiers) were used in alternative measurement setup instead of impedance transformers. This replacement was done for the 50 Omega differential mode insertion loss measurement setup. The performance of modified measurement setup was tested on several single phase EMI filters. The obtained data were compared with data taken in the setup with impedance transformers.