PROTECTING SWITCHING POWER SUPPLY FROM FAULT CONDITION

摘要

A switching regulator operating from a supply voltage for generating a drive signal in response to a feedback signal, comprising:
a timer circuit that monitors a level of the supply voltage for providing a timer period at a first output of the timer circuit when the supply voltage reaches a first reference voltage; and
a detector circuit having a first input coupled for receiving the feedback signal and a second input coupled to the first output of the timer circuit for receiving the timer period, wherein the detector circuit counts occurrences of the feedback signal during the timer period and generates a fault signal as a result of the detector circuit counting a number of occurrences of the feedback signal during the timer period.