Patent ID: 8872445

Claim:
An LED driving circuit comprising: a rectifier having a positive output and a negative output; a first circuit which includes a first LED array connected to said rectifier, a first current detection unit for detecting current flowing from said first LED array to said negative output of said rectifier, and a first current limiting unit for limiting the current flowing from said first LED array to said negative output of said rectifier in accordance with said current detected by said first current detection unit; and a second circuit which includes a second LED array, a second current detection unit for detecting current flowing from said second LED array to said first current detection unit, and a second current limiting unit for limiting the current flowing from said second LED array to said first current detection unit, wherein said second current detection unit and said second current limiting unit are connected, together with said second LED array, in parallel with said first current limiting unit, a current path in which only said first LED array is connected to said rectifier and a current path in which said first LED array and said second LED array are connected in series relative to said rectifier are formed in accordance with an output voltage of said rectifier, and said first current detection unit, upon detecting current flowing through said first and second LED arrays, operates said first current limiting unit so as to effect switching to said current path in which said first LED array and said second LED array are connected in series relative to said rectifier.