In one embodiment the present invention includes an over-current protection method. The method comprises generating a switching signal, starting and stopping a timer, sensing a current through a switch, comparing a response time to a reference time, and generating an over-current alarm signal. The switching signal activates one or more switches in a switching regulator. The timer is started in response to the switch being activated and is stopped in response to the sensed current exceeding a threshold. The response time indicates the time period between the starting and the stopping of the timer. The over-current alarm signal is generated if the response time is less than the reference time.