Systems and methods for controlling the charge profile during the commutation event of a synchronous switching transistor in a regulator

摘要

The present invention provide systems and methods for reducing a reverse recovery current through a body diode in a synchronous switching transistor. An inductor is coupled in the commutation path of the body diode of the synchronous switching transistor. The inductor slows the rate of increase of the reverse recovery current to reduce avalanche effects in the synchronous switching transistor. This reduces the peak reverse recovery current through the body diode of the synchronous switching transistor when the body diode commutates, thereby reducing power dissipation in the main switching transistor. An inductor may be coupled to both switching transistors so that power dissipation is reduced if the regulator is operated as a buck or boost regulator. A diode and a reverse recovery switcher may be coupled to the inductor to transfer energy in the inductor back to the input or output capacitor after the body diode commutates.