公开(公告)号：US20170025958A1

公开(公告)日：2017-01-26

申请号：US14808184

申请日：2015-07-24

Applicant: Dell Products L.P.

Inventor： Wei Cheng Yu ,  Tsung-Cheng Liao ,  Merle Jackson Wood, III ,  Yan Yang ,  Keith J. Kasprzak

IPC: H02M3/335 ,  G06F1/32 ,  G06F1/26 ,  H02M1/32

CPC classification number: H02M3/33515 ,  G06F1/263 ,  G06F1/3287 ,  H02M1/32 ,  H02M2001/0009

Abstract: In accordance with embodiments of the present disclosure, a switch mode power supply may include a transformer, a controller configured to generate a periodic switching signal, a switching transistor coupled between a sense node and the transformer, primarily configured to prevent or permit current flow in the transformer primary winding in accordance with the switching signal, a sense resistor coupled to the switching transistor at a sense node, and a limit circuit configured to obtain a voltage of the sense node at a particular point of the switching period as an indicator of the primary winding current, detect a duration of a demagnetizing interval, and generate a limit signal, based on the sense node voltage and the demagnetizing interval, indicating a power supply output current exceeding a limit threshold.

Abstract translation: 根据本公开的实施例，开关模式电源可以包括变压器，被配置为产生周期性切换信号的控制器，耦合在感测节点和变压器之间的开关晶体管，主要被配置为防止或允许电流流过 根据切换信号的变压器初级绕组，耦合到感测节点处的开关晶体管的感测电阻器和被配置为在开关周期的特定点处获得感测节点的电压的限制电路，作为开关晶体管的指示器 初级绕组电流，检测去磁间隔的持续时间，并基于感测节点电压和去磁间隔产生限制信号，指示电源输出电流超过限制阈值。