Patent ID: 7154232

Claim:
An electronic ballast control operable to detect faults in a lamp driven by an electronic ballast, the control comprising: a comparator having a first input coupled to the lamp to obtain a lamp parameter value, and having a second input coupled to a threshold value for comparison with the lamp parameter value; a shutdown circuit coupled to an output of the comparator for shutting down the electronic ballast based on selective application of the output of the comparator; and an AC coupling element between the lamp and the comparator, whereby the lamp parameter value is AC coupled to the first input; wherein said electronic ballast control is comprised in an integrated circuit and said first input is coupled to the lamp by a single pin of said integrated circuit; said shutdown circuit being responsive to said first input at said single pin for shutting down said electronic ballast in response to any one of a lamp fault, lamp removal and an end-of-life condition.