A buck regulator is a kind of switching voltage regulator which converts an unregulated input voltage into a lower regulated output voltage. The current consumed by the voltage regulator can be divided into two parts, namely the power provided to the load and the power provided to the buck regulator itself.
During normal operation, when the current demanded by the load is in a certain range, the regulator can maintain a high converting efficiency because the power provided to the load is much higher than the power provided to the buck regulator itself. When the current demanded by the load is low, or even zero, the converting efficiency is much lower because much of the power provided from the supply is provided to the buck regulator itself.
In the interest of increasing efficiency of buck regulators when the current demand by the load is low, further developments in the area of buck regulators are desired.