Integrated Class-D audio amplifier virtual test for output EMI filter performance

This paper proposes a model based on the segmentation technique that can be used for electromagnetic interference (EMI) filter test by simulation. It is dedicated for systems with a differential output. The present approach proposes virtual measurement of the filter performance in the final application. Thus, the source emissions and the load impedance are taken into account. The proposed approach uses impedance matrices to model the passive parts of the system. A matrix calculation permits to associate these matrices and create a compact model. The impedance matrices and the converter output voltages are used for currents and voltages computation at all the system points. Finally, the proposed method is applied and validated on a Class-D amplification system. This method shows good accuracy on the [1kHz-120MHz] frequency band.