A study on suppression of common-mode current due to a trace on a PCB

摘要

Suppression of common-mode (CM) current on a feed cable due to a trace on a printed circuit board (PCB) is studied experimentally and with finite-difference time-domain (FDTD) modeling. Six kinds of different structure of PCBs were employed for the investigation of CM current. Results show that shielded structure is effective in suppressing the CM current which might be the source of CM radiation, as well as direct radiation from the trace. The terminating resistor is no effect on the suppression of CM current at all of the PCB structure. This study can be the basic consideration to realize a PCB structure which is effective on the suppression of the CM current.