Electrical environmental characteristics for automotive electric systems

The electrical environment is one of the most important factors in the design of high reliability electronic systems mounted on automobiles. Studies were made of the generation mechanisms and characteristics of both transients and high-frequency conducted noise generated in automotive electrical components. The high-frequency conducted noise data were obtained in terms of amplitude-frequency through real-time statistical treatment of the acquired data. The most important transient for automotive electronic systems has been found to be the alternator load dump transient caused by battery disconnection, and the most influential high-frequency conducted noise is caused by contact breaking. The high-frequency conducted noise characteristics can be expressed in the amplitude-frequency relation in the frequency range of 100 kHz-80 MHz.