Apparatus and methods for controlling voltage converter are provided. In an example, a switched-mode DC-DC voltage converter can include an inductor, at least four switches coupled to the inductor and configured to direct current through the inductor to provide a desired output voltage at an output voltage terminal of the voltage converter using an input voltage supply and a ground reference of the converter, and a controller circuit, configured to receive an indication of inductor current through the inductor and to use the slope of the inductor current to control a change between two operating modes of a group of operating modes that include a boost operating mode, a buck operating mode, and a buck-boost operating mode.