Automotive Fuses Advancements Automotive electronics engineers need to meet stringent automotive reliability standards for high-stress applications such as engine controls and battery-management systems. Automotive surface-mount fuses, located under the dashboard in a fuse box, are the go-to choice fault protection. Of these fuses, two types are most commonly used: solid body (chip) fuses or wire-in-air fuses. However, not only are surface-mount fuses different, those that are commonly used can have major drawbacks. For instance, the non- uniform performance of printed-circuit style ceramic fuses can lead to internal connection failure caused by mechanical/thermal stress (vibration or bending), or by common soldering defects (cold joints or poor wetting). This type of failure can lead to damage to the circuit board and surrounding components. This article describes the trends in automotive electronics driving the need for more reliable surface-mount fuses, and explains why using conventional fuses to protect automotive applications can fall short. For a solution, it presents advancements in ceramic and wire-in- air surface-mount fuses designed to specifically address the AEC-Q200 automotive standard. It also shows results from simulation tests that illustrate the significant advantages of using advanced technology over the traditional approaches. As cars get “smart” and “connected,” more and more embedded and distributed electronics require pc-board-mounted circuit protection. And with the rapid emergence of electric (EV) and hybrid electric (HEV) vehicles – most with high energy lithium battery systems – the demand for reliable circuit protection devices to protect against catastrophic failures is critical. Evolution in Surface-Mount Fuse Technology While most automobiles (and commercial vehicles, for that matter) provide passengers with a comfortable environment, automotive applications for electronics are subjected to among the harshest of environments – wide temperature variations, shock and vibration, exposure to humidity, water and salt. These applications have placed emphasis on the need for improving surface-mount fuse technology. Fortunately, advancements in both chip and wire-in-air fuse technology is offering dramatically better reliability results over traditional solutions. Karl Kruse Karl Kruse GmbH & Co KG Schirmerstrasse 59 40211 Duesseldorf Germany +49 (0)211-27403530 +49 (0)211-27403533 info@kruse.de