In some electrical systems, disconnecting a supply line is necessary. This may be in the form of cutting off a battery voltage to retain the battery charge, for example, or separating a load from a live line. Ideally, this involves a mechanical switch.
However, if switching should occur via an electrical signal, an electronic switch is usually more suitable. Such an electronic switch can be built with a MOSFET as a switching element. In addition to a purely discrete solution with a MOSFET, numerous semiconductor ICs are available for easy implementation of an electronic switch.