Home / Automotive / Low EMI automotive power designs

Low EMI automotive power designs


Introduction


As automobiles continue to add an ever increasing number of electronic systems to enhance safety, comfort, efficiency and performance while minimizing harmful exhaust emissions, it comes as no surprise that they require physically smaller power solutions with dramatically higher power levels. Additionally, with the proliferation of more EMI-sensitive systems within the vehicle, reducing EMI emissions from switching power supplies is of paramount importance, thereby creating more challenges for switching regulator IC design.

According to Strategy Analytics, “the demand for enabling semiconductor devices is expected to grow at a CAAGR (compound average annual growth rate) of five percent per year over the next seven years, with the total market worth over $41 billion by 2021, compared to $28.9 billion in 2014. The Strategy Analytics analysis also identifies that demand for microcontroller and power semiconductors will drive over 40 percent of revenues.”

 

Strategy Analytics provides a very quantitative description of forecasting the growth of electronics content in automobiles, but more interesting is the prevalent role that power ICs play in this growth. These new power IC designs must offer the following:

 
1)      Robust performance across a wide range of voltages, including handling of transients in excess of 36V

2)         Ultralow electromagnetic interference (EMI) emissions

3)      The highest efficiency possible to minimize thermal issues and optimize battery run time.

4)      The smallest solution footprints, demanding very high power densities with switching frequencies of 2MHz or greater needed to keep the switching noise out of the AM Radio band while keeping solution footprints very small

5)      Ultralow quiescent current (10µA) to enable always-on systems such as security, environmental control and infotainment systems to stay engaged without draining the vehicle’s battery when its engine (alternator) is switched off  
 

The goals for the increased performance levels of power ICs are to enable the design of increasingly complex and numerous electronic systems. Applications fueling this growth are found in every aspect of the vehicle. For example, new safety systems, including lane monitoring, adaptive safety control, automatic turning and dimming headlights. Infotainment systems (telematics), which continue to evolve and pack more functionality into an already tight space, must support an ever growing number of cloud applications.

Advanced engine management systems with the implementation of stop/start systems and electronics laden transmissions and engine control, plus drive train and chassis management aimed at simultaneously improving performance, safety and comfort. A decade ago, these systems were only found in high-end luxury cars but are now commonplace in automobiles from every manufacturer; further accelerating automotive power IC growth. Figure 1 below shows the multitude of electronic systems that are typically found in today’s cars.

         

 

Figure 1. Electronic Systems Proliferation in Automobiles

 

Scroll To Top