Bootstrap pre-charging slow start charging circuit

• Main Authors: YANG JINHOU, PAN JIN, WANG YANG, KANG KAI, WANG GUIQI
• Format: Patent
• Language: Chinese; English
• Published: 31.12.2019
• 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 relates to a bootstrap pre-charging slow start circuit, which comprises a pre-charging circuit, a time delay circuit and a soft start charging circuit based on MOS transistor control. The slow start circuit for preventing overcurrent impact is arranged between a high-voltage power supply and a high-capacity capacitive load CL; when the high-voltage power supply is connected to the circuit and outputs voltage, the circuit charges the CL through the pre-charging circuit; meanwhile, a bootstrap capacitor is charged through the time delay circuit, conduction of the MOS transistor iscontrolled through the voltage of the bootstrap capacitor, the magnitude of loop current is controlled through the switching effect of the MOS transistor, the purpose of slow start is achieved by controlling the charging time of the bootstrap capacitor, and the effect of preventing circuit overcurrent from damaging a power supply is achieved. Compared with the traditional existing slow start circuit, the bootstrap pre-cha