| 主权项 |
1. A control circuit that forms a synchronous rectifier circuit together with a bridge circuit, wherein the bridge circuit comprises:
a first transistor arranged between a first input node and a rectification node; a second transistor arranged between a second input node and the rectification node; a third transistor arranged between the first input node and a reference node; and a fourth transistor arranged between the second input node and the reference node, and wherein the control circuit comprises:
a first variable voltage source that generates a first threshold voltage which is variable;a first zero current detection comparator that compares a first voltage at the first input node with the first threshold voltage, and that generates a first detection signal having a first level when the first voltage is higher than the first threshold voltage, and having a second level when the first voltage is lower than the first threshold voltage;a first adjustment comparator that compares the first voltage with a first reference voltage;a first adjustment unit that adjusts the first threshold voltage generated by the first variable voltage source, based on an output of the first adjustment comparator; anda control logic that switches a state of the bridge circuit according to the first detection signal. |
