An apparatus for delivering power to a load, which comprises an isolated power converter that converts input power on a primary side to output power and a supply voltage at a node on a secondary side. On the secondary side, a load switch is located on a current path to the load. A secondary-side control circuitry controls the load switch to operate in an ON mode in which current is provided to the load, and in response to a fault condition corresponding to an effective sudden disconnection of the supply voltage, switches the load switch into an OFF mode in which the current path to the load is blocked.