Lighting device and illumination fixture using the same

摘要

[Object] To provide a lighting device capable of reliably detecting existence or absence of load connection. [Means for Settlement] There are provided a DC-DC converting circuit 1 for converting a DC voltage between input terminals A and B and outputting the DC voltage to between output terminals C and D, a DC current carrying element (resistor R3) connected between the output terminals C and D, a load terminal 3 to which a semiconductor light-emitting element 4 lighted by a DC current supplied from the output terminals C and D is connected, a load connection detecting circuit 2 forming a path for passing the DC current from the input terminals A and B through the load terminal 3 and the semiconductor light-emitting element 4, and a rectifying element (diode D3) connected between the load terminal 3 and the DC current carrying element (resistor R3), the rectifying element blocking a path for passing the DC current from the input terminals A and B to the load connection detecting circuit 2 through the DC current carrying element (resistor R3).