Patent ID: 8004198

Claim:
A ballast for driving a lamp comprising: a rectifier connected to a power source, the rectifier configured to receive electricity from the power source and to generate a DC bus voltage upon receiving electricity; a driver circuit configured to receive the DC bus voltage from the rectifier and to generate a lamp voltage to drive the lamp upon receiving the DC bus voltage; a controller configured to control the driver circuit, said controller to monitor a first value corresponding to the DC bus voltage and to monitor a second value corresponding to the lamp voltage, wherein when the controller detects a fault condition, the controller disables the driver circuit for a preset period of time and thereafter resets to control the driver circuit to drive the lamp, and wherein when a ratio of the second value to the first value falls below a threshold value, the controller resets to control the driver circuit to drive the lamp; and a current reduction circuit configured to accelerate the resetting of the controller in the event of a fault condition, wherein the current reduction circuit reduces the second value supplied to the controller in a period of time that is less than the preset period of time, such that the ratio of the reduced second value to the first value falls below the threshold value, causing the controller to reset.