CONTROLLING REVERSE CURRENT IN SWITCHED MODE POWER SUPPLIES TO ACHIEVE ZERO VOLTAGE SWITCHING

摘要

A switched mode power supply includes a multilevel buck power converter and a control circuit. The power converter includes a first buck circuit and a second buck circuit each having a power switch, a rectifier, and an inductor. The power supply may further include a resonant power converter coupled to the multilevel buck power converter. In some examples, the control circuit is configured to generate control signals for the first buck circuit's power switch and the second buck circuit's power switch to control the power converter, and adjust a switching frequency of the control signals to control the amount of reverse current flowing in the first buck circuit and the second buck circuit to achieve zero voltage switching of the first buck circuit's power switch and the second buck circuit's power switch. Other example multilevel buck power converters and power supplies are also disclosed.