Various embodiments provide a system comprising a regulator and one or more low-drop-out linear regulators for improved efficiency. In one embodiment, a system comprises a regulator and one low-drop-out linear regulator comprising a pass transistor, and furthermore, another transistor matched to the pass transistor except for size. The matching transistor provides information regarding the source-drain voltage drop of the pass transistor. A controller circuit makes use of this information to set the regulator's output voltage to improve the efficiency of the system. Other embodiments are described and claimed.