US Patent 7342762 Resettable circuit protection apparatus

A circuit protection device includes a solid-state resettable switch, a first terminal in electrical communication with a first portion of the switch, the first terminal configured to be connected to a load. A second terminal is placed in electrical communication with a second portion of the switch, the second terminal configured to be connected to a power source. A controller is configured to enable the switch to be opened if an accumulated energy meets or exceeds a preset I2t rating, the accumulated energy based on a current sensed from an electrical point between one of (i) the load and the switch or (ii) the voltage source and the switch.