With the arrival of 48 V boardnet systems, a new method for safely connecting and disconnecting high current loads — electric power steering, electric turbo charger, etc — to the battery is required due to arcing problems associated with using mechanical relays.

To address this issue, an electronic fuse (eFuse) on a compact, double-sided FR4 PCB with passive cooling has been designed to switch loads up to 200 A at 48 V. This design also features a pre-charge function to limit any potential inrush current to an acceptable level, and continuous current measurement for use by the vehicle’s body control module to monitor battery health. This presentation will demonstrate the benefits of this innovative design.