Patent ID: 8446133

Claim:
A method of controlling a buck-boost converting circuit to supply a regulated output voltage at an output node of the buck-boost converting circuit, the buck-boost converting circuit comprising an inductive element, a first conduction controlling element coupled between an input node of the buck-boost converting circuit and a first terminal of the inductive element, a second conduction controlling element coupled between the first terminal of the inductive element and a reference voltage node, a third conduction controlling element coupled between a second terminal of the inductive element and the reference voltage node, and a fourth conduction controlling element coupled between the second terminal of the inductive element and the output node, the method comprising: controlling the first conduction controlling element and the third conduction controlling element to be electrically conductive and controlling the second conduction controlling element and the fourth conduction controlling element to be electrically nonconductive according to a first duty setting; determining a second duty setting, wherein generation of the second duty setting is independent of generation of the first duty setting; controlling the first conduction controlling element and the fourth conduction controlling element to be electrically conductive and controlling the second conduction controlling element and the third conduction controlling element to be electrically nonconductive according to the second duty setting; and controlling the second conduction controlling element and the fourth conduction controlling element to be electrically conductive and controlling the first conduction controlling element and the third conduction controlling element to be electrically nonconductive according to a third duty setting which is based on the first duty setting and the second duty setting.