Control circuit for switching regulator, switching regulator and electronic equipment using the control circuit

摘要

The invention improves the voltage regulation rate of the switching regulator in lag control. A divided output voltage divided by the first resistor and the second resistor is input to a first polarity input terminal of a comparator. A driver is used for controlling a switching transistor and a synchronous rectified transistor according to an output pulse of the comparator. A feedback circuit is used for outputting a switching signal to the reverse input terminal of the comparator according to the output pulse, wherein the switching signal is used for switching two voltage levels between the input voltage and a ground voltage. The error amplifier is used for amplifying an error between the divided output voltage and a first reference voltage and generating a second reference voltage to output to a second polarity input terminal of the comparator.

主权项

1. A control circuit for controlling at least one switching transistor of a switching regulator receiving an input voltage and generating an output voltage, comprising:
a first resistor and a second resistor for dividing the output voltage of the switching regulator; a comparator having a first polarity input terminal input a divided output voltage divided by the first resistor and the second resistor; a driver for controlling the switching transistor according to an output pulse of the comparator; a feedback circuit for outputting a switching signal to the first polarity input terminal of the comparator according to the output pulse, the switching signal for switching two voltage levels between the input voltage and a fixed voltage; and an error amplifier for amplifying an error between the divided output voltage divided by the first resistor and the second resistor and a first reference voltage and generating a second reference voltage to output to a second polarity input terminal of the comparator.