Patent ID: 11888395
Assignee: CHENGDU MONOLITHIC POWER SYSTEMS CO., LTD.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 14:
15. A control method used in a switch mode power supply, wherein the switch mode power supply has a power switch and converts an input voltage into an output voltage by controlling the power switch, the control method comprising:
engaging a control loop having an error amplifier to control the power switch, wherein the error amplifier has a first input terminal, a second input terminal and an output terminal;
coupling a first compensation network between the first input terminal and the output terminal of the error amplifier, or coupling a second compensation network to the first input terminal of the error amplifier; and
detecting whether the switch mode power supply enters a transient state, if the switch mode power supply enters the transient state, increasing a first resistance of the first compensation network or decreasing a second resistance of the second compensation network; wherein
when the output voltage decreases and the switch mode power supply enters the transient state, a positive voltage is provided to the second input terminal of the error amplifier; and wherein
when the output voltage increases and the switch mode power supply enters the transient state, a negative voltage is provided to the second input terminal of the error amplifier.