ADAPTIVE SYNCHRONOUS RECTIFIER CONTROL

摘要

The embodiments herein describe a switched mode power converter. In particular, the embodiments herein disclose techniques for adaptive synchronous rectification control. The switched mode power supply includes a synchronous rectifier controller that determines when to turn off the synchronous rectifier during each switching cycle based on a reference signal corresponding to when substantially all the power stored in a transformer of the power supply has been delivered to an electronic load. The synchronous rectifier controller may determine whether to adjust the reference signal used by the synchronous rectifier controller to turn off the synchronous rectifier during subsequent switching cycles.

主权项

1. A switching power converter comprising:
a magnetic component coupled to an input voltage and an output of the switching power converter; a switch coupled to the magnetic component, energy stored in the magnetic component when the switch is in an on state; a first controller configured to generate a first control signal to turn on or turn off the switch at each switching cycle of the switch to maintain regulation of the output of the switching power converter during a discontinuous conduction mode of the switching power converter; a synchronous rectifier switch coupled to the output of the switching power converter; a second controller configured to generate a second control signal to turn on or turn off the synchronous rectifier switch at each switching cycle of the synchronous rectifier switch; wherein the second controller is configured to turn off the synchronous rectifier switch during a first switching cycle of the synchronous rectifier switch based on a comparison of a reference signal and a drain-to-source voltage of the synchronous rectifier switch during the first switching cycle; and wherein the second controller is configured to determine whether to adjust the reference signal used by the second controller to turn off the synchronous rectifier switch during a second switching cycle subsequent the first switching cycle.