Fuses

Fuses protect electrical devices and components from overcurrents and short circuits that occur in improperly operating circuits. When fault current reaches a predetermined magnitude for a fixed period of time, current flow is interrupted through the melting of an internal element.
Fuse types can be miniature, subminiature or micro, midget, automotive, blade type, PC board, and protective. Miniature cartridge fuses are commonly available in dimensions of 5x20mm and 6.3x32mm. Subminiature fuses have very small dimensions (no principal dimension greater than 10 mm) and are ideal for compact circuit board layouts. Subminiature fuses are also called microfuses. Midget refers to 13/32" diameter fuses. Automotive fuses are specifically for use in automobiles. Blade-type fuses are typically used in low voltage, high current applications. PC board fuses are specifically for use on PC boards. Protective fuses are used for protection of secondary circuits or low voltage ICs.