Patent ID: 8482940

Claim:
An illumination lighting device, comprising: a power converter circuit having a configuration in which an input terminal to which a power supply can be connected and an output terminal to which a load circuit including at least a lamp can be connected are galvanically insulated, and having a power regulating function required by the lamp; output detection portion which is provided at the output terminal of the power converter circuit and has first current detection portion and second current detection portion; and a control circuit for regulating an output of the power converter circuit based on a result of detection performed by the output detection portion, wherein one end of the output of the power converter circuit is connected to one end of the load circuit via the first current detection portion, one end of an input of the power converter circuit is connected to the one end of the load circuit via the second current detection portion, the output detection portion has the result of the detection which is a synthesized signal of detection outputs of the first current detection portion and the second current detection portion, a current pathway, through which a ground-fault current flows from the one end of the input of the power converter circuit to the one end of the output of the power converter circuit via the first current detection portion and the second current detection portion, is formed when a ground fault occurs at a load terminal of the load circuit, and a detection signal of the first current detection portion and a detection signal of the second current detection portion that result from the ground-fault current are of additive polarities.