| 摘要 |
PROBLEM TO BE SOLVED: To improve an illumination quality by preventing a difference in brightness of LEDs from being generated in a case where LED lighting devices of a plurality of specifications that have different output voltages are connected with a DC power supply with a dimming function to drive individual LED illumination loads, in a non-insulation type LED lighting device in which a ground potential of a control IC is taken from a high-side of an output of a buck converter. ! SOLUTION: A buck converter 10, and a control IC 11 on/off controlling a switching element Q1 in the buck converter 10 in a PWM system, are connected between DC input terminals T1p and T1n and output terminals T2p and T2n. A ground terminal of the control IC 11 is connected with a high side of an output voltage of the buck converter 10. An input voltage width detection circuit 13 detecting an input voltage width between the input terminals T1p and T1n is provided. A photocoupler 14 (an insulation type signal communication eleme |
