Systems and methods for regulating power conversion systems with output detection and synchronized rectifying mechanisms

摘要

System and method for regulating a power conversion system. A system controller for regulating a power conversion system includes a first controller terminal and a second controller terminal. The system controller is configured to receive at least an input signal at the first controller terminal, and generate a gate drive signal at the second controller terminal based on at least information associated with the input signal to turn on or off a transistor in order to affect a current associated with a secondary winding of the power conversion system. The system controller is further configured to, if the input signal is larger than a first threshold, generate the gate drive signal at a first logic level to turn off the transistor.

主权项

1. A system controller for regulating a power conversion system, the system controller comprising:
a first controller terminal; and a second controller terminal; wherein the system controller is configured to:
receive at least an input signal at the first controller terminal; andgenerate a gate drive signal at the second controller terminal based on at least information associated with the input signal to turn on or off a transistor in order to affect a current associated with a secondary winding of the power conversion system; wherein the system controller is further configured to:
if the input signal is larger than a first threshold, generate the gate drive signal at a first logic level to turn off the transistor; andif the input signal changes from a first value larger than a second threshold to a second value smaller than the second threshold, change the gate drive signal from the first logic level to a second logic level to turn on the transistor.