PCB Electromagnetic Compatibility Design
PCB electromagnetic compatibility refers to the ability of electronic devices if they can function properly in complex electromagnetic environments. The purpose of electromagnetic compatibility design is to make electronic equipment not only suppress a variety of external interference, but also reduce the electromagnetic interference from one electronic equipment to other electronic equipment.
In a finished PCB board, there is more or less electromagnetic interference among adjacent signals which also called crosstalk. The magnitude of crosstalk is related to the distributed capacitance and distributed inductance between the loops. To solve this mutual signals of PCB electromagnetic interference, EPCB suggests the following measures:
Choose a reasonable PCB wire width: The impact of transient currents on printed lines is mainly caused by the inductive component of the printed conductors, and the inductance is proportional to the length of the printed conductors and inversely proportional to the width. Therefore, the use of short and wide wire to suppress interference is beneficial. Clock leads and bus driver signal lines often have large transient current, thus the wire should be as short as possible. For discrete components circuit, printed wire width of about 1.5mm can meet the requirements; for integrated circuits, printed wire width between should be between 0.2mm ~ 1.0mm.
Well-shaped mesh wiring structure: The specific way is to vertical wiring on the layer which is closely next to a horizontal wiring layer on a PCB board.
PCB thermal design: In order to facilitate the thermal dissipation, it’s better to pay attention to components arrangement as per the PCB layout rules. In the horizontal direction, high-power components are arranged as close as possible to the PCB board edge which can shorten the thermal transfer path. Temperature-sensitive components should be placed in the relatively low temperature area, and never put them directly on those components which release large amount of thermal.