In some boost converter applications, an input voltage normally exceeds a regulated output voltage. The operation of the boost converter in this condition can be referred to as a pass-through operation. Using various techniques, the efficiency of a pass-through operation of a synchronous boost regulator circuit can be greatly improved. For example, a synchronous boost regulator circuit can include an input voltage VIN to output voltage VOUT voltage comparator that can accurately monitor the output voltage to detect the pass-through operation. In a pass-through operation, the high-side switch can be kept ON to maintain high efficiency, and the quiescent current of the regulator circuit can be minimized by setting portions of the control circuit into a sleep mode.