Control Circuit with Short-circuit Protection for Current Sense Terminal of Power Converters

摘要

A control circuit includes a detection circuit to detect the short-circuited of a current sense terminal of the power converter. It includes a comparator, a verification circuit and a timer circuit. The comparator receives an input signal for generating a sense signal. The input signal represents the switching current of a power switch. The sense signal is enabled when the input signal is lower than a threshold. The verification circuit generates a protection signal in response to the sense signal or/and -a delay signal. The protection signal is generated when the current sense terminal is short-circuited, in which the power switch and the sense signal are enabled after the time delay of the delay signal. The protection signal turns off the power switch for the protection.