公开(公告)号：US20180248398A1

公开(公告)日：2018-08-30

申请号：US15726791

申请日：2017-10-06

Applicant: STMicroelectronics S.r.l.

Inventor： Alfio Pasqua ,  Michele Grande ,  Salvatore Tumminaro

IPC: H02J7/00 ,  H02J7/04

CPC classification number: H02J7/0072 ,  H02J7/0006 ,  H02J7/0024 ,  H02J7/0057 ,  H02J7/022 ,  H02J7/04 ,  H02J7/045 ,  H02J2007/0062 ,  H02M3/33507 ,  H02M2001/0032 ,  H02M2001/0038 ,  Y02B70/16

Abstract: In some embodiments, a power supply, for example, for battery chargers of mobile telephones, includes: a control circuit having a driving terminal coupled to a control terminal of a power transistor, where the power transistor drives a primary winding of a transformer of the power supply; a current sense input for detecting a first current flowing through the power transistor; and a switched signal generator coupled to the driving terminal, the switched signal having a period that is the sum of an active time, a dead time, and a demagnetization time of the transformer. The control circuit also includes a control network coupled to the current sense input and to the switched signal generator; a regulating network having a detection unit configured to detect the first current reaching a lower limit; and a variation unit configured to increment the dead time when the active time reaches the lower limit.