Patent ID: 8879283

Claim:
A system for protecting a power converter, the system comprising: a first comparator configured to receive a first threshold signal and a first signal and to generate a first comparison signal, the first signal being associated with an input current for a power converter; a second comparator configured to receive a second threshold signal and the first signal and to generate a second comparison signal, the second threshold signal being different from the first threshold signal in magnitude; a detection and delay component configured to receive at least the second comparison signal, detect, with or without a predetermined delay of time, the second comparison signal only if one or more predetermined conditions are satisfied, process information associated with the detected second comparison signal, and generate a first detection signal based on at least information associated with the corresponding detected second comparison signal before the predetermined delay of time; a switch signal generator coupled to at least the detection and delay component and configured to generate a switch signal for controlling a switch for adjusting the input current for the power converter based on at least information associated with the first comparison signal and the first detection signal; wherein: the switch signal generator is further configured to generate the switch signal to turn off the switch if the first comparison signal indicates the first signal is larger than the first threshold signal in magnitude; the switch signal generator is further configured to generate the switch signal to turn off the switch if the first detection signal indicates the first signal is smaller than the second threshold signal in magnitude before the predetermined delay of time; wherein the detection and delay component includes a deglitch component and a latch component, the latch component being coupled, directly or indirectly, to the deglitch component; wherein: the deglitch component is configured to cause the predetermined delay of time; the latch component is configured to generate the first detection signal; wherein: the detection and delay component further includes a timer component coupled to the latch and configured to receive the first detection signal; the timer component is further configured to, if the first detection signal indicates the first signal is smaller than the second threshold signal in magnitude before the predetermined delay of time, output a reset signal to the latch component after a predetermined period of time.