A system and method control an output voltage across a load using current mode control to control current through an output filter connected to the load. The output voltage across the load is compared with a reference voltage to generate a reference current signal indicative of a desired average current through the load. A control signal is generated to indicate when an output current is greater than the desired output current. The output filter is alternately coupled to a first supply rail and to a second supply rail in response to the control signal to generate an average current through the load.