A controller for a SIMO DC-DC converter operable in CCM and DCM receives a signal representative of an inductor current, and signals representative of a first and a second DC-DC converter output. The controller has a first and second output adapted to control electronic switches coupled to a first and second output filter, and a third and fourth output adapted to control current in an inductor. The controller controls the outputs based upon the inputs by determining a desired PWL inductor current and current waveform, and determines pulsewidths of the outputs, to match the inductor current to the desired PWL. A timer controls pulsewidths of the outputs and the controller dynamically selects DCM or CCM to maintain the first and second DC-DC converter outputs at predetermined levels. In embodiments, the desired PWL inductor current is one or both of a desired valley current and a desired peak current.