A device for controlling a switching mode power supply includes a regulation module, a feedback node, and a resistance module. The regulation module is adapted to cause a switching module to selectively couple, based on an oscillation frequency, a primary side winding of a transformer and a supply to control a voltage, current, or power output at a secondary side winding of the transformer. The feedback node is adapted to receive an indication of a voltage at the secondary side winding of the transformer. The resistance module is adapted to selectively set a pull-up resistance based on a comparison between a time-controlled frequency and a voltage-controlled frequency that is generated based on a voltage at the feedback node, wherein the regulation module is adapted to set the oscillation frequency as the time-controlled frequency or the voltage-controlled frequency.