公开(公告)号：US20210135575A1

公开(公告)日：2021-05-06

申请号：US17144323

申请日：2021-01-08

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

Inventor： Jie Ren ,  Yanjun Hu ,  Xue Zhang

IPC: H02M3/158 ,  H02M1/08

Abstract: A control circuit applied to a power adapter includes a voltage conversion unit and a switch control unit. The voltage conversion unit is configured to: receive a first direct current voltage, and generate a second direct current voltage based on the first direct current voltage, where when the first direct current voltage is lower than a working voltage of the switch control unit, the voltage conversion unit is configured to boost the first direct current voltage, to obtain the second direct current voltage. The switch control unit is configured to: receive the second direct current voltage from the voltage conversion unit, and use the second direct current voltage as a power supply voltage of the switch control unit.