Patent ID: 7834828

Claim:
An LED driving semiconductor apparatus for driving at least one LED connected in series with each other and connected to an output terminal via a coil, said LED driving semiconductor apparatus comprising: an input terminal connected to a high voltage side of a rectifying circuit which rectifies an alternating current voltage inputted from an AC power source and outputs a direct current voltage, said input terminal being provided for inputting the voltage from said rectifying circuit; an output terminal connected to one end of said coil, said output terminal being provided for supplying a current to said at least one LED; a switching element block connected between said input terminal and said output terminal, said switching element block having a first switching element; and a controller including a regulator and a drain current detector, said regulator inputting the voltage at said input terminal as an input voltage and generating a power source voltage for driving and controlling said switching element block using the input voltage, said drain current detector detecting a drain current of said switching element block, said controller performing on/off control of said first switching element with a predetermined frequency to block the drain current of said switching element block when the drain current reaches a predetermined threshold.