Vendors of switching regulators are very active in the development of leading-edge control circuits to help engineers address specific design challenges. 

No control mode is optimal for every application, and the various control modes for non-isolated step-down DC/DC controllers and converters each have unique advantages.

Linear control modes such as voltage mode and peakcurrent mode have been used for decades, and many designers are familiar with their implementation. However,over the past few years, nonlinear control modes such as constant on-time and its derivatives have become more popular due to their simplicity and better load-transient performance.