Control device and control method of power converter and switching power supply using the same

摘要

The disclosure relates to a control device, a control method of a power converter and a switching power supply using the control device. The control device of the power converter includes: a first control unit, which is coupled to the power converter to detect an output voltage of the power converter and is configured to generate a first control signal based on the output voltage; a variable resistor unit, which is connected to an output terminal of the first control unit to receive the first control signal and is configured to generate a resistance value based on the first control signal; and a second control unit, which is connected to the variable resistor unit and is configured to output a second control signal in order to control operations of a switch unit of the power converter.

主权项

1. A control device of a power converter, wherein the power converter comprises a switch unit, wherein the control device comprises:
a first control unit, which is coupled to the power converter to detect an output voltage of the power converter and is configured to generate a first control signal based on the output voltage; a variable resistor unit, which is connected to an output terminal of the first control unit and is configured to generate a resistance value based on the first control signal; and a second control unit, which is connected to the variable resistor unit and is configured to output a second control signal to the switch unit in order to control operations of the switch unit, wherein the power converter further comprises a transformer, a first terminal of the variable resistor unit is connected to a primary winding of the transformer, and a second terminal of the variable resistor unit is connected to a first ground terminal.