common mode currents

Audio rectification is a common EMI problem in which high-frequency RF signals interfere with low-frequency audio circuits, producing audible noise or distortion. This article explains the causes of audio rectification, demonstrates TDMA/GSM effects on speakers, and offers practical EMI mitigation techniques for designers.

Why do cables radiate? Common mode currents are the culprit. Through four practical experiments, learn how return paths, grounding switches, and parasitic capacitances determine whether your current stays differential—or becomes a radiating common mode problem.