Method and circuit for optimizing efficiency in a high frequency switching DC-DC converter

摘要

A switch control (12) circuit which optimizes the efficiency of a buck or boost converter by eliminating simultaneous conductive states of the main power transistor (16) and the synchronous rectifying transistor (18). Power dissipation of the synchronous rectifying transistor (18) is minimized by reducing the amount of time (Td1 and Td2) that the intrinsic body diode of transistor (18) conducts current. Charge control circuit (53) is utilized for boost converter operation and charge control circuit (118) is utilized for buck converter operation.