The SMD100F-2 with Resettable Fuses - PPTC 30V 40A IMAX is a surface mount device from Littelfuse designed to provide overcurrent protection. It features an IMAX of 40A and a rated voltage of 30V with reliable resettable protection of electronic circuits, and offers a fast, accurate and secure method of protecting against both overloads and short circuits. The power fuse has a unique solid-state design that includes an organic polymer which senses both current and temperature and responds by rapidly increasing its resistance. As a result, heat is dissipated, and the current is reduced to the desired level. This device also offers a very fast response time and current limitation. It is suitable for use in a variety of applications including automotive, consumer, IT, medical, power, and more.