A Practical Technique Using Planar Coils to Make the Radiated Immunity of Specific Integrated Circuit Pins Less Dependent From PCB Orientation

In this article, an inexpensive passive approach is proposed, both making the immunity of integrated circuits (ICs) less dependent on their orientation and controlling specific pins. This technique based introduction planar 2-D coils surrounding microcontroller ( $\boldsymbol{\mu}$ C) at printed circuit board (PCB) level. The importance coil physical parameters (geometry, resonant frequency, orientation) as well interference frequency investigated, evaluating difference in magnetic field pin interest two opposite orientations (i.e., 0 notation="LaTeX">$^\circ$ 180 ). effectiveness proposed demonstrated full-wave simulations measurements, showcasing provided improvement through monitoring behavior sensitive Besides, article strongly recommends IC designers not to place power supply pins close corners C package due presence highest local tangential when no structures are implemented. Coil shown be key adjustment parameter enhance any pin. found relevant than its geometry distance with respect using octagonal was also effective a wide range (from 210 least 500 MHz). Compared no-coil case, enhancement 74.2% (27.5%) achieved measurement (simulation) by addition PCB, which clearly demonstrates relevance that simple for practical use highly electronics.