Fuse

A fuse is an electric / electronic or mechanical device, which is used to protect circuits from over current, overload and make sure the protection of the circuit. Electric fuse was invented by Thomas Alva Edison in 1890.In electronics and electrical engineering, a Fuse is an electrical safety device that operates to provide overcurrent protection of an electrical circuit. Its essential component is a metal wire or strip that melts when too much current flows through it, thereby stopping or interrupting the current. It is a sacrificial device; once a Fuse has operated it is an open circuit, and must be replaced or rewired, depending on its type.

eFuses, or electronic fuses, are integrated circuits that can replace larger conventional fuses or other protection devices such as resettable polymeric fuses. Housed in small plastic packages, such as DFN and Flip-chip, they integrate a control circuit and a power switch with low on-resistance, connecting the input port to the load.

Fuses have been used as essential safety devices from the early days of electrical engineering. Today there are thousands of different fuse designs which have specific current and voltage ratings, breaking capacity, and response times, depending on the application. The time and current operating characteristics of fuses are chosen to provide adequate protection without needless interruption. Wiring regulations usually define a maximum fuse current rating for particular circuits. Short circuits, overloading, mismatched loads, or device failure are the prime or some of the reasons for fuse operation. When a damaged live wire makes contact with a metal case that is connected to ground, a short circuit will form and the fuse will melt.