Based on the statistics concerning traditional electronics fields and applications (like computers, communications, consumer), they’re coming close to saturation. Even smart phones that have been regarded to be growing at a high race suffer from decline. However, automotive electronics is exclusive.
The leading drive for rocketing of automotive electronics derives from higher demand of electronics that needs to be applied for vehicles, ranging from manual shift to automatic shift, from FM radio to video player, air conditioner, power window, engine control, cruise control, air bag, GPS, LED lighting, automatic speed and distance control, driving record, or even auto-driving vehicles etc.
Automotive electronics consists of such a wide range of applications that electronic devices are applied in all parts of a vehicle. Apart from traditional electronic sections, automotive electronics also include digital-controlled computer system, vehicle-mounted mobile communication equipment, vehicular audio system, video system and air conditioner etc. The performance and function implementations of all the systems depend on PCBs (Printed Circuit Boards) whose reliability finally contributes to or even determines the performance of automotive vehicles.
Development Trend of Automotive Electronics
It’s been estimated that the market share of automotive electronics systems will rise by 6.3% in 2019 and the CAGR (Compound Annual Growth Rate) will reach 6.4% during the period from 2017 to 2021, featuring a higher speed than other electronic systems. In addition, the market share of automotive electronics in all electronics market has been annually increasing and it’s estimated that it’ll reach 9.9% by 2021 from that of 9.1% in 2017.
The global automotive electronics has reached 206.33 billion US dollars in 2016 and by the year of 2024, it is estimated that the number will surpass 395.91 billion US dollars with a CAGR approximately 6.9%.
Demanding Requirement for Future Automotive PCB
Due to the particularity on functions of automotive vehicles and extreme environment vehicles will work in, automotive PCBs have to be compatible with the requirement of automotive industry on both quality and reliability, playing a crucial role in electronics system.
The special requirement automotive PCBs have to meet includes temperature, humidity, vibration, high power and current, high heat, high frequency, high-speed signals, high density and miniaturization. Therefore, the demanding requirement of automotive PCBs includes the following items:
• High temperature
• High humidity
• High speed
• High stability
When it comes to electric vehicles, however, the requirement has to be higher. Electric vehicles have to be capable of standing current as high as hundreds consistently for about 1 million hours and high voltage as high as 1,000 volts. Automotive PCBs working for autonomous cars have to be able to withstand a high voltage as high as hundreds so as to ensure their reliability.
To better serve autonomous vehicles, automotive PCBs have to meet higher requirement in numerous fabrication technologies. The layer count should be increased. Line width, spacing and through-hole aperture should be reduced in order to be compatible with smaller size. The real estate of copper on circuit board should be increased in order to dissipate more heat in time. To achieve higher requirement in terms of high speed and high frequency, impedance control should be increased and new material should be applied in order to make PCB produce high running speed.
High speed and high frequency are needed by automotive PCB to complete signal transmission between interior sections of vehicles and exterior surroundings. For example, interconnection or image recognition will feature a speed as high as 10GHz in future and high-speed radar will feature a frequency as high as 77GHz. Thus, automotive PCBs should feature not only excellent signal integrity and power integrity, but high-quality EMC (Electromagnetic Compatibility) as well. Additionally, material has to be strictly selected. Apart from electrical performance, material’s stability has to be guaranteed in terms of temperature, humidity and bias voltage.
As far as the devices are concerned closest to heating source in vehicles, it’s quite ordinary for them to reach an operation temperature that is as high as 120℃. For example, automotive LEDs (Light Emitting Diodes) call for flexible substrate material with high heat dissipating capability. Advanced safety detection system calls for increasingly higher requirement on both thermal cycle and electrical transfer between fine lines. As the advanced automotive electronics applications become more complex and minimized, PCB density will go up while PCB size down.