Cost-effective means of protecting electronics from voltage transients and overvoltages in an automotive network

The electronics fitted in an automobile need to be protected from voltage surges and overvoltages exhibited by car battery systems. These may have dangerous consequences to expensive electronic control units (ECU's) that require stable voltage supplies. The power regulating system outlined in this paper offers an inexpensive method for providing the necessary protection by utilizing a conventional transient voltage suppression (TVS) avalanche diode as well as employing a novel shutdown mechanism using a relay to allow disconnection of the ECU'S from the car battery, if required. This unit has given appropriate results when used to protect tracking units installed in the automobile.