公开(公告)号：US20140247031A1

公开(公告)日：2014-09-04

申请号：US13782223

申请日：2013-03-01

Applicant: ANALOG DEVICES TECHNOLOGY

Inventor： SONG QIN

IPC: H02M1/32 ,  H02M3/156

CPC classification number: H02M1/32 ,  H02M3/1588 ,  Y02B70/1466

Abstract: A negative current protection system for a low side switching converter FET, for use with a switching converter arranged to operate high and low side FETs connected to an output inductor to produce an output voltage. The negative current protection system comprises a current sensing circuit which produces an output Vcs that varies with the current in the high side FET, a negative current threshold generator which produces a threshold signal −Ith which represents the maximum negative current to which the low side FET is to be subjected, and a comparison circuit arranged to compare the valley portion of Vcs and −Ith and to set a flag if Vcs

Abstract translation: 一种用于低侧开关转换器FET的负电流保护系统，用于与连接到输出电感器的高低侧FET连接以产生输出电压的开关转换器。 负电流保护系统包括电流检测电路，其产生随着高侧FET中的电流而变化的输出Vcs;产生阈值信号的负电流阈值发生器，其表示低边FET的最大负电流 并且比较电路被布置为比较Vcs和-Ith的谷部分，并且在开关周期中的预定时间（通常在转换器的消隐时间之后）设置Vcs <-Ith的标志。 当标志置位时，系统优选地通过调节开关FET的操作来减小负电流来进行响应。