Basic load switches consist of four pins: input voltage, output voltage, enable and ground. When the device is enabled via the ON pin, the pass FET turns on, thereby allowing current to flow from the input pin to the output pin, and power is passed to the downstream circuitry. Integrated load switches are electronic switches that can be used to turn on and turn off power supply rails in systems, similar to a relay or a discrete FET. Load switches offer many other benefits to the system some including protection features that are often difficult to implement with discrete. Isolation switches, also known as disconnector switches or isolators, are mechanical switching devices designed to ensure that an electrical circuit can be completely de-energized for safe maintenance, inspection, or repair work. Diodes Incorporated's DML series is one such example of integrated load switches. It can interrupt a certain level of load current and overload current, but cannot interrupt short-circuit current. This system is significantly smaller than the traditional discrete configuration.
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