As the number of semiconductors increases and in-vehicle communications become more complex due to the spread of electric vehicles and autonomous driving, the EMC for automotive electrical components is becoming more difficult as it must satisfy the semiconductor level beyond the existing vehicle level.

Yeon Gyu-bong, a senior researcher at the Korea Automobile Research Institute, presented on the topic of 'Electromagnetic interference and EMI shielding in electrical components such as electric vehicles' at the '2024 e4ds Analog Day' held on December 10, and stated that EMC for automotive electrical components is becoming increasingly difficult.

According to Senior Researcher Yeon Gyu-bong, the power system for electric vehicles is increasing to high voltage, and as the voltage inside the vehicle increases to 350V and 680V, the electrical components must withstand up to 1,200V.In addition to the human component, the voltage going into the remaining node also increases to 60V, and considering the margin, it was revealed that development is underway up to 42V and 48V, and thus EMC considerations are increasing.

Along with this trend, the adoption of SiC (silicon carbide) semiconductors is increasing, and it was mentioned that the advantages of SiC, such as fast response and wide bandwidth, are actually increasing EMI, making EMC response more difficult.

He said that countermeasures are urgently needed because electromagnetic waves are emitted every time the voltage is quickly raised or lowered.

In addition, power line communication problems are also emerging. When charging power, various information such as billing and safety diagnosis are exchanged, and when a problem occurs on one side, the other side is blocked. However, although international standards have been established for communication, it is not being used properly in Korea, so a response to this is urgent, he said.

In addition, in the case of autonomous vehicles, at level 5, the vehicle must operate on its own without driver intervention. In this case, EMC is becoming more important to ensure safety. Additionally, with the spread of SDV, the vehicle architecture is also changing to a zonal architecture. In this case, the use of semiconductors and communication chips for vehicle control increases, and since semiconductors lead vehicle control, it is important to protect semiconductors from EMI. Therefore, it was mentioned that semiconductor-level EMC, not the existing vehicle-level EMC, is urgently needed.

In particular, as automakers have become much more conservative these days, they are demanding that semiconductor companies pass EMC tests on modules and other higher levels before delivery, and despite the existence of international standards, each automaker has its own standards, making it difficult to supply electrical components, he said.

In particular, as electrification accelerates, problems with static electricity are increasing, and 80% of EMI problems related to semiconductors He insisted that we must be thorough in our preparations for static electricity management, as it can cause static electricity problems.

Regarding communication lines, he said that most communication lines are made by twisting two wires together without shielding, and that in this case, they are vulnerable to EMI.

In this case, problems related to vehicle control are likely to occur, and in a situation where sensors for autonomous driving are increasing, if you pay attention to cable shielding, the weight of the vehicle increases and there are significant problems with fuel efficiency, so the current situation is to only meet the EMC limit.

Additionally, vehicles use a variety of communication protocols, all of which are connected to EMC, so this also needs to be taken into consideration.

In addition, reliability tests must be conducted for the supply of semiconductors and other electrical components, and it was advised that it is advantageous for supply to conduct reliability tests through a certified organization in order to satisfy the standards desired by automobile manufacturers beyond international standards.