Patent ID: 7576493

Claim:
A vehicle LED lamp controller, comprising: a DC power source; multiple LED elements; a starting circuit having an input and an output connected to multiple LED elements; a preheating circuit having an input connected to the DC power source and an output connected to the input of the starting circuit; and a current limitation circuit connected between the DC power source and the multiple LED elements, wherein the current limitation circuit automatically connects or disconnects a connection between the multiple LED elements and the DC power source according to changes of current supplied to the multiple LED elements, wherein the current limitation circuit comprises: an electronic switch connected to the multiple LED elements to decide whether the current of the DC power source is supplied to the multiple LED elements; a current detector connected between the electronic switch and the DC power source to detect the current supplied to the multiple LED elements through the electronic switch; a switch driver connected to the DC power source through the current detector and connected to the electronic switch to keep the electronic switch in a conducting condition when the current of the DC power source is normally supplied to the multiple LED elements; and a comparator connected to the current detector and the switch driver to control whether the electronic switch is conductive through the switch driver, according to the changes of current supplied to the multiple LED elements.