High efficiency PFM control for buck-boost converter

摘要

A buck/boost voltage regulator generates a regulated output voltage responsive to an input voltage and a plurality of control signals. The buck/boost voltage regulator includes a plurality of switching transistors responsive to the plurality of control signals. Control circuitry monitors the regulated output voltage and generates the plurality of control signals responsive thereto. The control circuitry controls the operation of the plurality of switching transistors to enable a charging phase in a first mode of operation, a pass through phase in a second mode of operation and a discharge phase in a third mode of operation within the buck/boost voltage regulator to eliminate occurrence of a four switch switching condition.