Secondary controller for use in a synchronous flyback converter, power converter, and method of controlling a synchronous flyback converter

摘要

PROBLEM TO BE SOLVED: To provide a secondary controller for use in a synchronous flyback converter that includes a comparator, a drive circuit and logic circuitry.SOLUTION: The comparator is coupled to generate a compare signal in response to a comparison of a threshold to an input signal representative of a secondary winding voltage of the synchronous flyback converter. The drive circuit is coupled to generate a drive signal to control a first switch to be coupled to a primary side of the synchronous flyback converter. The drive signal is coupled to be generated by the drive circuit in response to a feedback signal representative of an output of the synchronous flyback converter. The logic circuitry is coupled to the drive circuit and the comparator, and is also coupled to generate a control signal to control a second switch in response to the drive signal and the compare signal.SELECTED DRAWING: Figure 1