A switching power supply includes a circuit having at least two reactive components to provide an output voltage and capable of being switched from a first output state to a second output state. A switching component switches the circuit between at least two switching states including the first output state and the second output state. A pulse width modulator receives a duty cycle and drives the switching component to cause switching between two of the at least two switching states. A nonlinear controller component provides a duty cycle to the pulse width modulator. The duty cycle corresponds to at least one predetermined power supply state variable. The nonlinear controller component includes a processor to apply an optimization technique to minimize a predetermined function of the duty cycle and internal states of the power supply and to obtain a relationship between the duty cycle and at least one predetermined state variable.
