This document provides methods and apparatus configured to efficiently regulate an output voltage near a desired voltage level, for example, under varying input or load conditions. An example apparatus can include a regulator having a boost controller configured to provide voltage to an output of the regulator when at least one of the output voltage or the input voltage is below a first threshold voltage and a buck controller configured to provide voltage to the output of the regulator when at least one of the output voltage or the input voltage is above a second threshold voltage. Further, the regulator can be configured to provide the input voltage at the output of the regulator when at least one of the input voltage or the output voltage is between the first and second threshold voltages. In some examples, the first threshold is below the second threshold.