An apparatus and method for detecting an end of life (EOL) condition of a lamp that exhibits a re-ignition behavior. A voltage is applied to the lamp to cause the lamp to start emitting light, and a lamp re-ignition voltage to normal lamp voltage difference after a mask-off period expires is monitored. The lamp is determined to have reached the EOL condition when a predetermined percentage of high difference half cycles occur during a set number of lamp voltage half cycles that are measured during a measurement window. The method continuously monitors the lamp re-ignition voltage to normal lamp voltage difference and records whenever the lamp re-ignition voltage to normal lamp voltage difference is higher than the re-ignition difference threshold level at any lamp voltage half cycle. An EOL lamp is detected when a predetermined number of high difference half cycles occurs in a set total number of lamp voltage half cycles measured in a rolling measurement window.