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With the increasing content of electronics in automobiles and faster development times, it is essential that electronics hardware design and vehicle electrical architecture is done early and correctly. Today, the first designs are done in the electronic format with circuit and CAD design tools. Once the initial design is completed, several iterations are typically conducted in a “peer review” methodology to incorporate “best practices” before actual hardware is built. Among the many challenges facing electronics design and integration is electromagnetic compatibility (EMC). Success in EMC starts at the design phase with a relevant “lessons learned” data set that encompasses component technology content, schematic and printed circuit board (PCB) layout, and wiring using computer aided engineering (CAE) tools.

With the advent of vehicle manufacturer driven on-board charging systems for plug-in and extended range electric vehicles, such as the Chevrolet Volt, important considerations need to be comprehended in both the requirements specified as well as the test methodologies and setups for electromagnetic compatibility (EMC). Typical automotive EMC standards (such as the SAE J551 and SAE J1113 series) that cover 12 volt systems have existed for many years. Additionally, there has been some development in recent years for high voltage EMC for automotive applications. However, on-board charging for vehicles presents yet another challenge in adopting requirements that have typically been in the consumer industry realm and merging those with both the traditional 12 V based system requirements as well as high voltage based systems.

The proliferation of entertainment and communication systems in vehicles has led to increased concern as to the performance of these systems in an electromagnetic environment. One methodology used to assess radiated immunity performance on a component level is bulk current injection (BCI). In BCI a current probe is used to inject lower frequency radio waves (RF) onto the harness of an automotive device under test. This is an indirect methodology given that on a vehicle level a direct radiated field is impinged on the vehicle rather than a coupled current such as in BCI. Because of that, important considerations need to be taken into account to replicate the vehicle coupling phenomena on a component test. This paper examines setup issues and assesses the effectiveness of the BCI methodology for immunity testing of infotainment systems.