Abstract: An adaptive dead time (ADT) control scheme for use with a switch mode power converter having a full bridge with synchronous rectifiers topology. A controller which implements the control scheme includes an input circuit arranged to receive a signal representative of the converter's output voltage, and an output circuit arranged to operate the converter's switching elements and synchronous rectifiers to produce a desired output voltage. The controller is further arranged such that the converter's “dead time” is adaptively varied in an inverse relationship to the magnitude of the load current. In a preferred embodiment, the signals used to operate the synchronous rectifiers are PWM signals, and the controller adaptively varies the dead time in a linear inverse relationship to the magnitude of the load current by modulating the rising and falling edges of the signals used to operate the synchronous rectifiers.

Abstract: An adaptive dead time (ADT) control scheme for use with a switch mode power converter having a full bridge with synchronous rectifiers topology. A controller which implements the control scheme includes an input circuit arranged to receive a signal representative of the converter's output voltage, and an output circuit arranged to operate the converter's switching elements and synchronous rectifiers to produce a desired output voltage. The controller is further arranged such that the converter's “dead time” is adaptively varied in an inverse relationship to the magnitude of the load current. In a preferred embodiment, the signals used to operate the synchronous rectifiers are PWM signals, and the controller adaptively varies the dead time in a linear inverse relationship to the magnitude of the load current by modulating the rising and falling edges of the signals used to operate the synchronous rectifiers.