Upcoming regulations on greenhouse gas emissions and safety are driving a technological leap in the automotive industry. Electrical powertrains and their complement of 48-volt architecture, along with all the functions required for different levels of autonomous driving, contain a plethora of innovations aimed towards the stringent new requirements. Further electrification of the powertrain and surrounding systems requires a communication architecture to control the actuation and sensing. Electromagnetic noise is a key issue in any electrical power train, in either full electrical or hybrid architectures , since it affects the operation of the electronic circuits within the car. Countermeasures have to be taken at early stages of the design. Otherwise, projects face unacceptable risks of high engineering costs, wasted resources or project delays.
New 48-volt Electrical Architecture
The new 48-volt electrical architecture in cars pushes the envelope in terms of electromagnetic compatibility and safety requirements. New safety precautions are needed, since even a single malfunction between the 48-volt and the 12-volt electrical system, such as a short circuit, may damage the entire 12-volt system due to overvoltage. 1000BASE-RH, the Ethernet specification for a Gigabit capable, Plastic Optical Fiber-based (POF) communication protocol is optimal for the new architectures, as it provides intrinsic Electromagnetic Compatibility (EMC). Powertrains that are either fully electrical or hybrid profit from the natural galvanic isolation between communicating modules and radiation-free harness. With excellent performance in Electromagnetic Interference (EMI) and in Electromagnetic Susceptibility (EMS), these optical Ethernet links are ideal for communications between the 48-volt and the 12-volt domain. They provide 100 Mbps and 1 Gbps Ethernet compatible solutions today, and multi-gig in the future, with enough margin to withstand the harsh automotive environment. Its native galvanic isolation and mechanical robustness make optical Ethernet technology ideally suited for current and future in-vehicle network infrastructure. Applications such as Battery Management Systems (BMS) and Integrated Smart Antenna (ISA) modules profit from the inherent electromagnetic compatibility of POF.