POWER SUPPLY AND LUMINAIRE

摘要

PROBLEM TO BE SOLVED: To provide a lighting device to which an LED load of a wide output power range can be connected, without requiring an exclusive design of a power-factor improvement circuit according to the output power.SOLUTION: An LED lighting device 1-1 includes: a MOSFET 11; a current detection unit 37 for detecting the magnitude of a switching element current flowing through the MOSFET 11; a power-factor improvement circuit 2 having a control circuit 12 for improving the power factor by switching the MOSFET 11 on/off, and switching the MOSFET 11 off when the magnitude of a switching element current detected by the current detection unit 37 exceeds a predetermined threshold; a power supply voltage detection circuit 30 for detecting the magnitude of an input voltage input by the power-factor improvement circuit 2; and a current value adjustment unit 60 for adjusting the magnitude of a switching element current detected by the current detection unit 37 depending on the magnitude of an input voltage detected by the power supply voltage detection circuit 30.