Class III compensation network and switching power supply

Abstract

The invention discloses a class-III compensation network and a switching power supply. The class-III compensation network comprises a voltage dividing branch and a compensation branch, the voltage dividing branch is connected between the output end and the ground, and the voltage dividing branch is provided with a voltage dividing node connected with a reference voltage; the first capacitor and the second capacitor are connected between the output end and the voltage dividing node in series, one end of the third resistor is connected to the connecting position of the first capacitor and the second capacitor, one end of the third capacitor is connected with the other end of the third resistor and the COMP end of the switching power supply, and the other end of the third capacitor is grounded. According to the III-type compensation network and the switching power supply, the voltage output by the output end can meet the requirement by adjusting the voltage dividing branch and combining the given reference voltage; the compensation branch is matched with the voltage dividing branch to carry out double-zero-point and double-pole compensation, it is ensured that when the required voltage output by the output end is small and close to the reference voltage, enough gain margin and phase margin can be achieved, and the stability of the system is ensured.

Description

technical field [0001] The invention relates to the field of integrated circuits, in particular to a type III compensation network and switching power supply. Background technique [0002] In order to ensure the output gain margin and phase margin of the switching power supply, it is often necessary to introduce a compensation network. As the application scenarios change, customers have different requirements for the output voltage of the switching power supply. When the output voltage required by the customer is relatively small and close to the reference voltage of the switching power supply, the compensation effect of the existing III compensation network will be weakened and cannot guarantee sufficient gain margin and phase margin. [0003] The information disclosed in this Background section is only for enhancing the understanding of the general background of the present invention and should not be taken as an acknowledgment or any form of suggestion that the informati...

AI Technical Summary

Problems solved by technology

When the output voltage required by the customer is relatively small and close to the reference voltage of the switching power supply, the compensation effect of the existing III compensation network will be weakened, and sufficient gain margin and phase margin cannot be guaranteed.

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