Offline power converters draw very small amounts of power when unloaded or inactive (no load demand), power consumption may be further reduced by allowing the start-up controller and/or secondary-side controller to enter into a sleep mode (functions within the controllers shut down). When the energy storage capacitors for either the start-up controller or the secondary-side controller reach a low state-of-charge, either controller can wake itself and the other controller, thereby allowing the power converter to become active until both energy storage capacitors are refreshed enough for the controllers to go back into a low power sleep mode. This cycle, which draws very little average power from the AC line, continues until the power converter is required to remain awake (operational mode) and deliver power to the load.