公开(公告)号：US09673722B2

公开(公告)日：2017-06-06

申请号：US14738984

申请日：2015-06-15

Applicant: LITE-ON TECHNOLOGY CORP.

Inventor： Wing-Keung Eng ,  Po-Jung Tseng ,  Wei-Lieh Lai

IPC: H02M3/335 ,  H02M3/337 ,  H02M1/00

CPC classification number: H02M3/3376 ,  H02M2001/0032 ,  H02M2001/0054 ,  H02M2001/0058 ,  Y02B70/1433 ,  Y02B70/1491 ,  Y02B70/16

Abstract: A quasi-resonant half-bridge converter includes a switch unit including first and second switches that are coupled in series, a capacitor unit coupled to the switch unit in parallel, a rectifier unit, an output capacitor, and a transformer coupled to the aforesaid components. The first and second switches are respectively controlled using first and second control signals that have a constant frequency. Duty cycles of the first and second control signals may be adjusted based upon a DC output voltage across the output capacitor for promoting conversion efficiency of the converter when operating at light load.