Differential mode noise on the PCB´s signal traces converted from external common mode noise

This study experimentally clarifies the relationship between the common mode noise induced on the cable connected to the signal trace of PCB and the differential mode noise on signal trace, converted from the common mode noise, due to the unbalance of differential signal trace by applying the measurement method that Test baluns are used as a load of the cable and a signal source. In this study, S13 (Differential mode noise) and S23 (Common mode noise) are measured by the network analyzer for evaluation. Finally, the effectiveness of the common mode choke on signal trace and the shielding for the cable for both common mode and differential mode noise reduction are evaluated.