公开(公告)号：US20240146205A1

公开(公告)日：2024-05-02

申请号：US18473221

申请日：2023-09-23

Applicant: Richtek Technology Corporation

Inventor： Shin-Li Lin ,  He-Yi Shu ,  Shih-Jen Yang ,  Ta-Yung Yang ,  Yi-Min Shiu ,  Chih-Ching Lee ,  Yu-Chieh Hsieh ,  Chao-Chi Chen

IPC: H02M3/335 ,  H02M1/00

CPC classification number: H02M3/33592 ,  H02M1/0032 ,  H02M1/0045

Abstract: A flyback power converter includes a power transformer, a first lossless voltage conversion circuit, a first low-dropout linear regulator and a secondary side power supply circuit. The first low-dropout linear regulator (LDO) generates a first operation voltage as power supply for being supplied to a sub-operation circuit. The secondary side power supply circuit includes a second lossless voltage conversion circuit and a second LDO. The second LDO generates a second operation voltage. The first operation voltage and the second operation voltage are shunted to a common node. When a first lossless conversion voltage is greater than a first threshold voltage, the second LDO is enabled to generate the second operation voltage to replace the first operation voltage as power supply supplied to the sub-operation circuit; wherein the second lossless conversion voltage is lower than the first lossless switching voltage.