Control circuit of power adapter

• Main Authors: TANG JIANFU, CHEN YAOZHOU
• Format: Patent
• Language: Chinese; English
• Published: 27.07.2016
• Subjects: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC,OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWERSUPPLY SYSTEMS; CONTROL OR REGULATION THEREOF; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION

The invention provides a control circuit of a power adapter. The power adapter comprises an inductor, a power switch, and a feedback circuit. The control circuit comprises an input signal detection circuit, which is used to detect input signals to generate detection signals; a clock generating circuit, which is used to generate clock signals; an error detection circuit, which is used to generate error signals according to reference signals and feedback signals; a control signal generating circuit, which is used to control the switching frequency of the power switch according to the clock signals and the error signals; a reverse adjusting circuit, which is used to adjust the clock generating circuit or the control signal generating circuit according to the detection signals, and is used to set the switching frequency of the power switch in the inverse ratio to the input signal. The control circuit is used to determine the optimal switching frequency of the power switch dynamically according to the input signal