Patent ID: 7990125

Claim:
A power supply regulator, comprising: a comparator having first and second inputs and an output, the first input of the comparator adapted to sense a current flow through a switch, the second input of the comparator adapted to sense a variable current limit value; and a controller coupled to the output of the comparator and to the switch to control switching of the switch to regulate an output of a power supply in response a feedback signal, wherein the controller disables the switch if the sensed current flow through the switch is greater than the sensed variable current limit value, wherein the variable current limit value is set to a first variable current limit value by the controller in response to an input line voltage of the power supply if there is not an over current condition during a first switching cycle that occurs after a skipped switching cycle of the switch, and wherein the variable current limit value is set to a second variable current limit value by the controller in response to the input line voltage if there is the over current condition during the first switching cycle that occurs after the skipped switching cycle, wherein the over current condition occurs when the current through the switch exceed the variable current limit value before a maximum on time of the switch occurs during a switching cycle of the switch, and wherein the first variable current limit value is greater than the second variable current limit value.