Today’s electrical and electronic devices are subject to mandatory EMC requirements throughout the world. Many devices operate at high frequencies and are very small. They are placed in nonconductive plastic cases providing no shielding. Essentially, all these devices cannot meet these mandatory requirements or they may cause interference to other devices or receive interference causing susceptibility problems without a proper program of EMI control. This program consists of identifying the “suspect” components and circuits that may cause or be susceptible to EMI. This is completed early on in the program to allow for an efficient design in keeping the cost of dealing with EMI as low as possible. A complete EMC program consists of proper filtering, grounding and shielding. This article will discuss the latter, but the other factors cannot and will not be ignored or given insufficient priority.
The automotive industry has changed drastically in recent years. Advancements in technology paired with tighter federal fuel and emissions regulations have resulted in the need to place more electrical systems into vehicles. This in turn places a greater emphasis on keeping the Electromagnetic Interference (EMI) of these systems from interfering with each other through radiated and conducted emissions, as well as crosstalk between the multitudes of on-board systems.