A driver circuit for an electronic switch, the driver circuit having a first input for receiving a first control signal, and a second input for receiving a signal from a current sensor, the driver circuit further including a shut-off circuit for operating the electronic switch to cause an interruption to current flow in the event of a fault condition arising, such as current through the electronic switch exceeding a predetermined threshold, wherein operation of the shut-off circuit can be invoked by a predetermined event at the first input.